During the stripping of the roof skin off the Cougar, I also discovered a few pieces that were a bit different than the ones on my Torino that I wanted to use. I snagged the larger vacuum canister that was on top of the drivers side wheel well and also the one mounted to the back portion of the wheel well under the fender. I cut a section out of the upper portion of the driver's side fender to use as material to form a patch panel for the rust hole in the lower section of my passenger side front fender and that's how I gained access to the "hidden" canister.
While I had my arm inside the fender, I noticed that the Cougar had a hard plastic rear fender cap to seal the backside of the fender area at the door hinge post. Once I had the canister out of the way, I dropped my trouble light into the opening to get a better look at the plastic piece. It looked like it was in usable condition, so I removed the attaching hardware and pulled it out to see if it would fit on the backside of the Torino fender. While it didn't follow the contour of the Torino fender exactly, it did line up with the holes and locator tab opening already stamped into the fender structure. I installed it loosely to confirm it would work and then I cut a matching hole in the upper portion of the passenger fender so I could remove that side as well. Here are a few shots of the rigid plastic fender seal and insulation.