Wow great job Sam your work is flawless along with you photography skills to capture it all to boot. They make Evergreen ribbed plastic stock that I think would be perfect in modifying the cover with, I will dig some up tomorrow and post, I used it as grills on 1:43.
What use to add tremendous time on this build was the body work along with making the wheels and grills...all the things in the kit. You now have loads of extra time.
Here's my opinion or what I know of the existing pics of the "Movie" car..facts. As you know 11 cars were made, but only three had the full suspension mods for all the stunts. Of those three two were destroyed in filming which leaves 1 actual running survivor. I also believe of the total 11 only 3 survived after filming. I also know that CVS kept that one remaining running car after filming which was the one that was eventually sold yrs later on ebay. The running survivor was an auto all cars were autos, only the rigged(non functional) prop cars were manuals.
So IMO the only car that wouldn't be damaged would be the car just used in driving straight and fast...which in my mind would be the "movie" correct car. The trans kit provides everything necessary to make a "movie" correct exterior. There are well documented pics for interior along with the movie clips.
The following pics(close you eyes Sam)...are from one of the original press release photo shoots and yrs later of that same car when sold on Ebay, which is above mentioned CVS car. Don't be scared away from this cover either, It would be just about the same mods as you intended just add photo etched mustang script...see below.
Don't fret my father in law and brother in law own and operate a thophy engaving shop. I will run it by them and see if we can photo etch a few covers tomorrow.