Greetings Max Power,
My post is of the FWIW variety. I'm new to the forum and to Mustang ownership. Mine is a '69 Sportsroof. It originally came with a 302/FMX that was traded out for a 351W/C4. I do not know when that work was done or any other details of the engine. At this point all I know about the engine is that it isn't stock!
One of the first things I noticed as I went about assessing my cars condition and prioritizing repairs was that the radiator shroud was broken - and pretty apparently from impact by the fan. I purchased a replacement from CJ Pony and gave it a close visual inspection upon its arrival. It is virtually identical in dimensions to the original part. I installed it and upon powering up noticed the "tick tick" of the fan hitting the shroud. I took everything apart and double-checked verifying that I had assembled everything correctly. I called CJ Pony and was assured that I have purchased the correct shroud. I removed it again and then removed the radiator and inspected the radiator support - no indications of damage or modification. I put everything back together (again!), this time putting as much downward pressure as possible on the shroud. It didn't make a lick of difference.
So I modified the shroud by slotting the bolt openings. it didn't take much and now the fan doesn't hit the shroud. This is not what I would call optimal or permanent. There is obviously something wrong here but as a new owner, I am still in the "sorting things out" stage.
The picture you posted is identical to the condition of my car. The fan sits too low inside the shroud. It also doesn't extend far enough into the shroud. I could modify that but any attempt to extend the fan would only nullify the modifications I've made.
My car runs at a gauge -indicated slightly above midpoint going down the road, but will drift into the danger zone if I get stuck in heavy stop n go traffic. My current intention is to add an electric pusher fan to assist in those heavy traffic moments. I have followed this thread very carefully and it has given me food for thought on other things to check and test before going down that particular path. In my modest opinion the relationship of the fan to the shroud is the primary culprit for the failure of the car to maintain proper temperature control. I am open to the possibility of other factors being contributory.
My post is by way of saying that your circumstance is not an isolated one. I wish you luck in your pursuit of a solution and strongly suspect that it will also be the solution to mine.
thanks for reading,
Axio