Check out what I did last week.
No photos of the process, but I removed the old seat cover. It had been spraypainted black but was original. It had been disintegrating rapidly. It was a thermally sealed cover made of 4 main pieces plus a pocket at the nose of the seat. After getting it off, I carefully cut down the center of each heat sealed seam line and heated the pieces with a heat gun and let them flatten out being pressed between pieces of plywood under weight. I took the pieces in the best shape and used them symmetrically to trace new onto the back of the vinyl. Then I added 1/2" seam allowance to the sewn areas and stapled it together using a regular paper stapler, and ran it through by brand new industrial grade heavy duty walking foot sewing machine, and ran a top stitch over that. Installing it was painful due to a defective Arrow T-50 staple gun that was shooting bunches of 5 staples at a time. Rode out to get an alternative and painfully stapled it on. I need a pneumatic one soon. Heated the cover once on with the heat gun again to let the vinyl relax a bit. After stretching it on it pulls the seat smaller. Looking good now though!
I offer my service to anyone in need of a seat cover. I've been making these for a couple years now. Watch for the bags I'll be making as well.