[A bones]

There are books around that explain the process. The main thing, I believe is to have a helper, work from front to back, and go slowly. My plan involves marking off the center line of the material, and to look to borrow flat benches for me, and the helper to stand on.
The material is pulled from both sides at the same time, securing the header section first.
Then slowly step at a time move to the rear. Don't overlook the padding. Ford used some kind of cotton stuff.

Since no one sees it I plan to use that extra foll of fiberglas insulation that's in the rafters of my garage.
Have fun.