My roommate owns a 1965 Ford Country Sedan, and I'm the mechanic. He got it 15 years ago and it was his daily driver for several years. But, some issues have come up that I'm trying to straighten out so it can be put back to use. Since the vehicle spent most of its life in Washington (originally owned by the American Red Cross) and the fuel filler door seal rotted, it's allowed water to get trapped in the left rear quarter panel and rust it out. I recently removed the rusted and leaking fuel tank, had it stripped to clean metal, filled the rust holes with J-B Weld (since you apparently can't get a good replacement tank and the shops all said it was too bad to repair), and then painted it with gas-resistant engine paint. Now I have to figure out how to make a new fuel filler door seal, because of course, you can't buy new ones. But, this is a complicated design. I got some new rubber sheet and will attempt to make it work, but I am unsure how well the corners will turn out, plus it needs to have a drain at the bottom and somehow seal against the filler neck. Any ideas? I'm surprised how few parts are available for this car, and how challenging it's been to finish basic repairs.