A while back, the new Trucks TV (or whatever it's called now) they did a segment on refurbishing a square Chevy seat. It was on "Project Nighttrain" Anyway, they bought cushions and covers from a supplier like or somewhere, then showed you how to do all the stretching and use the hog rings to clip it all back to the frame. Looked easy enough. I'll likely try when I start redoing one of my trucks.