rwcstang

Just realized I had a some night shots.
 

if I were to do this all over again, I would rebuild locally with an experienced machine shop, they can do the same build and you can buy parts and have them install it.
Most online crate engines are affordable but some companies use a mix of off-shore/brand name parts to keep cost down. 
only issue I have with online crate motors if something goes wrong with the engine, you have to take it out (or pay someone to take it out) and ship it back to them for repair, which takes more time and money.
 

maybe incorrect seals?
Disc Brake Distribution Block and Proportioning Valve Rebuild - How To
 

agreed, Im going this route once I go EFI, the stealth tank can handle both EFI and Carb Set ups. its matter of getting a fuel regulator and correct hose.  

to answer your first question: 
my current 392w stroker had a "street fighter" c4 from performance automatic with a 2500 stall convertor and I had stock open 3:00 diff, it was a good platform and nothing ever broke as I was on street tires. I would definitely look into performance automatic if you decided to stay with the c4 or you can buy their 4spd auto. I decided to go manual as that was the original goal, so I went with a TKO0600 and went with a trutrac ford 9 w/3:50 gears. I was able to put down 360rwhp and 400rwtq after dyno and tune.
if there was a 5-6 speed auto that could fit with no cutting/mods I would have gone this route.
For the 302/351w:
both 302//351w are great platforms, though the power you are wanting to make, I think the 331 should be easy build, but the 302 block has limitations if you are trying to achieve max power, thats when the 351w comes in to play, they can take up to 600hp no problem. 
price is roughly the same with both engines, with a 351w you are limited to intake options, if you stay with the stock hood, I wanted the edelbrock airgap but I read there was clearance issues with the stock hood and some ppl recommended going with a cowl hood. I went with the weiand stealth intake instead, to keep my stock hood and I make good power overall.
the 302's are easier to work on, they are smaller and no clearance issues, 
351w are somewhat wider and taller and can get tight under the hood if you go with big heads and headers, servicing the 351w can be tiresome, which is why some ppl tend to stay with a 302 but 351w can take more power. 
of course, these opinions can be eliminated if you went with a dart block, then I suggest going with the 331. 
 

Pro touring is the look I'm going for.
69-70 coupes always go to the poormans 302/429 boss look. I wanted to be different, wanted to add a bit of mordern ford OE Parts and color. Inspiration came from the cali special, new edge fr500 concept and the termy 03-04 cobra. Silver and Black wheels look so good!
just a summary of what I went with:
393w stroker (dyno 360 RWHP, 400RWTQ) TKO600 kit from MDL Street or Track Front Coil over suspension w/ Bilstein Sport Shocks 4.5 Mid eye Grab-a-Track Leaf springs w/Bilstein Sport shocks Vintage Venom (RIP) 03-04 Cobra front and rear brake kit Ford 9 TruTrac w/3:50's Dakota RTX Gauges (still getting used to this, but so far its great!) Vintage Venom front and rear 03-04 cobra brake kit 18x9/10 FR500's from americanmuscle.com 245/275x40x18 BFGoodrich Sport Comp 2 Summer Tires Ford Ingot Silver, Paint Code UX  

Pro touring is the look I'm going for.
69-70 coupes always go to the poormans 302/429 boss look. I wanted to be different, wanted to add a bit of mordern ford OE Parts and color. Inspiration came from the cali special, new edge fr500 concept and the termy 03-04 cobra. Silver and Black wheels look so good!
just a summary of what I went with:
393w stroker (dyno 360 RWHP, 400RWTQ) TKO600 kit from MDL Street or Track Front Coil over suspension w/ Bilstein Sport Shocks 4.5 Mid eye Grab-a-Track Leaf springs w/Bilstein Sport shocks Vintage Venom (RIP) 03-04 Cobra front and rear brake kit Ford 9 TruTrac w/3:50's Dakota RTX Gauges (still getting used to this, but so far its great!) Vintage Venom front and rear 03-04 cobra brake kit 18x9/10 FR500's from americanmuscle.com 245/275x40x18 BFGoodrich Sport Comp 2 Summer Tires Ford Ingot Silver, Paint Code UX  

Pro touring is the look I'm going for.
69-70 coupes always go to the poormans 302/429 boss look. I wanted to be different, wanted to add a bit of mordern ford OE Parts and color. Inspiration came from the cali special, new edge fr500 concept and the termy 03-04 cobra. Silver and Black wheels look so good!
just a summary of what I went with:
393w stroker (dyno 360 RWHP, 400RWTQ) TKO600 kit from MDL Street or Track Front Coil over suspension w/ Bilstein Sport Shocks 4.5 Mid eye Grab-a-Track Leaf springs w/Bilstein Sport shocks Vintage Venom (RIP) 03-04 Cobra front and rear brake kit Ford 9 TruTrac w/3:50's Dakota RTX Gauges (still getting used to this, but so far its great!) Vintage Venom front and rear 03-04 cobra brake kit 18x9/10 FR500's from americanmuscle.com 245/275x40x18 BFGoodrich Sport Comp 2 Summer Tires Ford Ingot Silver, Paint Code UX  

Pro touring is the look I'm going for.
69-70 coupes always go to the poormans 302/429 boss look. I wanted to be different, wanted to add a bit of mordern ford OE Parts and color. Inspiration came from the cali special, new edge fr500 concept and the termy 03-04 cobra. Silver and Black wheels look so good!
just a summary of what I went with:
393w stroker (dyno 360 RWHP, 400RWTQ) TKO600 kit from MDL Street or Track Front Coil over suspension w/ Bilstein Sport Shocks 4.5 Mid eye Grab-a-Track Leaf springs w/Bilstein Sport shocks Vintage Venom (RIP) 03-04 Cobra front and rear brake kit Ford 9 TruTrac w/3:50's Dakota RTX Gauges (still getting used to this, but so far its great!) Vintage Venom front and rear 03-04 cobra brake kit 18x9/10 FR500's from americanmuscle.com 245/275x40x18 BFGoodrich Sport Comp 2 Summer Tires Ford Ingot Silver, Paint Code UX  

Replaced my old gauges with Dakota Digital RTX Vintage Series. Definitely and awesome product, super easy to calibrate on your phone. 

Replaced my old gauges with Dakota Digital RTX Vintage Series. Definitely and awesome product, super easy to calibrate on your phone. 

Replaced my old gauges with Dakota Digital RTX Vintage Series. Definitely and awesome product, super easy to calibrate on your phone. 

Definitely worth it. Only thing I wish it had was the running horse when the high beam goes on

Replaced my old gauges with Dakota Digital RTX Vintage Series. Definitely and awesome product, super easy to calibrate on your phone. 

Replaced my old gauges with Dakota Digital RTX Vintage Series. Definitely and awesome product, super easy to calibrate on your phone. 

Replaced my old gauges with Dakota Digital RTX Vintage Series. Definitely and awesome product, super easy to calibrate on your phone. 

a friend of mine, who loves photography took pictures of my car. 
looks pretty good! 
 

a friend of mine, who loves photography took pictures of my car. 
looks pretty good! 
 

a friend of mine, who loves photography took pictures of my car. 
looks pretty good! 
 

a friend of mine, who loves photography took pictures of my car. 
looks pretty good! 
 

a friend of mine, who loves photography took pictures of my car. 
looks pretty good! 
 

a friend of mine, who loves photography took pictures of my car. 
looks pretty good! 
 

Looks great.

stock rods are adjustable, but if you looking for performance, they won't hold poly's, I would toss the stock strut rods and go with Street or Track; https://www.streetortrack.com/Street-or-Track-Adjustable-Strut-Rods-pr-16135.html if you are staying with the stock suspension. 
 

I have a 393w with 195 avenger heads, weiand, stealth intake, holley 750 dp, march serp pulleys,  longs tubes with magnaflow xpipe with a tko600 a ford 9, 3:50 gears
I had a MDL kevlar, steel organic clutch, but clutch went out after a year, so im going with a mcleod super street pro clutch. hopefully this one will last longer. 
330rwhp 390+rwtq untuned dynojet dyno 
365rwhp 400rwtq tuned on a dynapack dyno