rharden 12 Report post Posted February 14, 2015 I have a 1970 Mach 1, 351 Cleveland engine with a top loader 4-speed. I bought a Hurst Comp Plus shifter and Hurst linkage kit many years ago. The kit is #3737717 and I thought they sent the correct one. Well, after all these years, I went to install it and it's not the correct kit. The Hurst web site says I need #3737637. The installation drawings/instructions show both of these kits mounting on the rear of the tail shaft. The shifter should mount closer to the trans mount area. I called Hurst, just to get their tech advice, and the guy said I need Hurst #3735587. Now I'm really confused. The Hurst guy tells me to order both the #3737637 and the #3735587 and mix and match what I need. That's spending around $400.00 on shifter kits. I think he's nuts. I'm installing a Gear Vendors Overdrive unit and the tail shaft they sent me is drilled with front and rear mounting holes. They said it is correct for a 1970 Mustang with a 351C engine. Does anyone out there know what Hurst kit is correct? My car was bought new in 1970 and it was built with a Ford 3-speed trans. I later installed a Ford toploader HEH out of a 1966 Ford Fairlane, 390. It was a perfect fit and I used a 1969 Ford Mustang shifter. Just a little history. Thanks. 1 Ronaldbaf reacted to this Quote Share this post Link to post Share on other sites
Ridge Runner 1,112 Report post Posted February 14, 2015 That is why. The Fairlane tail housing has a different mounting location for the shifter mounting than the Mustang tail housing .You need the adapter,probably the part number you were given . Quote Share this post Link to post Share on other sites
1969_Mach1 333 Report post Posted February 14, 2015 The close ratio top loader in my 69 Mach 1 is a 1968, and I believe, according to the tag on it, from a Ranchero. It only has one shifter mounting location and it is close to the rear of the tail shaft. It has been a long time so I don't have any part numbers, but I installed a Hurst Competition Plus shifter and the installation kit came with an aluminum plate that bolted to the tail shaft, then the shifter bolted to this adapter. I didn't have any issues. I remember it was confusing as to what kit I needed. Thankfully, the parts person was familiar with the setup. I will add, do not try to use the repro OEM style shifter boot for a Hurst shifter. That repro boot It is so rigid it tends to pull the Competition Plus shifter out of 4th gear. I used a Hurst boot and made a trim plate to fit it to the 4 original 1/4-20 mounting holes in the floor. it works great. Quote Share this post Link to post Share on other sites
Wycked69 20 Report post Posted February 15, 2015 If your toploader was truly from a 70 mustang with a 351C, then the tailshaft housing should be the one with the 3 mounting holes at the rear (C4DR-7A040A). These are 14" long tailshaft housings and are the same for all 65-70 mustangs having a SBF. Since you say the transmission you used was out of a 66 fairlane, the shifter location was different but the same location as the big block mustang. Therefore, you should only need the Hurst #3735587 which is for the big block. Quote Share this post Link to post Share on other sites
rharden 12 Report post Posted February 15, 2015 That is why. The Fairlane tail housing has a different mounting location for the shifter mounting than the Mustang tail housing .You need the adapter,probably the part number you were given . The Gear Vendors tail shaft housing has been drilled and tapped for mounting the shifter adapter to the front or rear of the housing. The problem I have is Hurst tells me what kit and shifter to use for my application, a 1970 Mustang with a small block. They don't say 351C, just a 351. The directions for the recommended Hurst kit, 3737637, shows the mounting plate mounted at the rear of the housing. That would put the shifter too far to the rear in order to line up with the floor opening. Even the other number Hurst gave me, 3735587, shows the mounting plate at the rear of the tail housing. I was just looking for someone, who owns a 70 Mustang with a 351C to say, this is what Hurst numbers I used. Quote Share this post Link to post Share on other sites
rharden 12 Report post Posted February 15, 2015 If your toploader was truly from a 70 mustang with a 351C, then the tailshaft housing should be the one with the 3 mounting holes at the rear (C4DR-7A040A). These are 14" long tailshaft housings and are the same for all 65-70 mustangs having a SBF. Since you say the transmission you used was out of a 66 fairlane, the shifter location was different but the same location as the big block mustang. Therefore, you should only need the Hurst #3735587 which is for the big block. The Gear Vendors tail shaft housing has been drilled and tapped for mounting the shifter adapter to the front or rear of the housing. Gear Vendors asked what trans I have and what the car is I'm installing their OD in. They tell me their tail housing is machined and drilled to match the original 70 trans housing. The 66 tail housing that was on the trans, C6OR-7A040-C, had the mounting holes to the front of the housing, with undrilled casting post to the rear. The problem I have is Hurst tells me what kit and shifter to use for my application, a 1970 Mustang with a small block. They don't say 351C, just a 351. The directions for the recommended Hurst kit, per their web site is 3737637, and it shows the mounting plate mounted at the rear of the housing. That would put the shifter too far to the rear in order to line up with the original floor opening. Even the other number Hurst gave me, 3735587, shows the mounting plate at the rear of the tail housing. I was just looking for someone, who owns a 70 Mustang with a 351C to say, this is what Hurst numbers I used. Quote Share this post Link to post Share on other sites
rharden 12 Report post Posted February 15, 2015 If your toploader was truly from a 70 mustang with a 351C, then the tailshaft housing should be the one with the 3 mounting holes at the rear (C4DR-7A040A). These are 14" long tailshaft housings and are the same for all 65-70 mustangs having a SBF. Since you say the transmission you used was out of a 66 fairlane, the shifter location was different but the same location as the big block mustang. Therefore, you should only need the Hurst #3735587 which is for the big block. I wrote back and answered two other responses. Do you own a 70 Mustang with a 351C? If so, what shifter are you using and where is it mounted on the tail housing? The rear mounting holes are there in the Gear Vendors housing, along with holes to the front side of the housing. All the Hurst linkage kits show the shifter mounted on the rear of the housing. I don't have the engine and trans installed at the moment, but just looking at the trans mount location would tell me the shifter has to be towards the front of the housing. I realize, this shouldn't be this difficult. Maybe I should just install everything, then figure it out. I thought it would be much easier to install the shifter on the trans while it's on the bench, adjust it and then remove it for installation. Quote Share this post Link to post Share on other sites
Wycked69 20 Report post Posted February 15, 2015 referring to 4-speed Toploaders Look at the attached chart from David Keys. The tail shaft housings circled in Red (C4DR-7A040-A, C4ZR-7A040-A) are those that were used on "ALL" small block ford mustangs from 65 thru 70. 260, 289, 302, 351W, 351C.The tail shaft housings circled in Green (C6OR-7A404-C, C7OR-7A404-A) are those used on 67 - 70 big block mustangs (390, 428, 429). The difference is the 390 sometimes used a 28 spline output shaft while the 428, 429 used the 31 spline output shaft. (ALL WERE 14" LONG TAILSHAFT HOUSINGS) If you installed a 4-speed toploader from a 66 Fairlane 390 to your 351C, it should have had the tail shaft housing C60R-7A404-C. My 68 had a 351C and Toploader 4-speed with a C4DR tailshaft housing and a hurst competiton plus shifter when I bought the car. It was mounted at the rear of the tailshaft housing. I rebuilt another toploader from a big block that had a tail shaft housing C6OR. Because I wanted to use an original top loader shifter, I had to install and adapter plate to move the shifter farther back at the tail shaft housing. (see photo's). The 67 - 70 mustangs are IDENTICAL with regards to engine size and shifter placement. In your case, if your motor was a 351C and you used a toploader with the C6OR tailshaft housing, then it would have had a bracket placing to the rear of the 14" housing whether it was a hurst or a toploader shifter. Even the link shows a photo of a toploader with a hurst mounting plate attached at the rear for the hurst shifter Quote Share this post Link to post Share on other sites
1969_Mach1 333 Report post Posted February 15, 2015 Maybe he has the wrong Competition Plus shifter itself and the shift lever doesn't have the correct bends to fit through the stock opening in the floor. I think the issue is simply the engine or trans is not installed yet and it just appears to not line if when mounted to the rear of the tail shaft. Install the motor and trans in the car then proceed with the shifter installation. Quote Share this post Link to post Share on other sites
rharden 12 Report post Posted February 16, 2015 Thanks everyone for the info and ideas. Wycked69, you really sent quite a good bit of info and pictures. I appreciate all the help. I think I'll install the engine and trans soon, once the weather warms up. I live in northern Illinois and it's too cold to keep the garage door open very long. Once everything is installed, I can get a better idea about the shifter mount and linkage. Thanks. Quote Share this post Link to post Share on other sites
1969_Mach1 333 Report post Posted February 16, 2015 You will probably be surprised how far forward the motor and trans sit in the car and that the rear shifter mounting location will work. Quote Share this post Link to post Share on other sites
RogerC 136 Report post Posted February 17, 2015 My hurst shifter is oem out of a 70 cougar. It sits all the way back on the tail housing and sits perfectly in the shifter hole in the trans tunnel. uses this mount plate mounted as shown here Quote Share this post Link to post Share on other sites
