Seat Covering Help...

Those seat foams made for a-b-c-bodies bucket seats will include instructions for shaving bolsters ,etc.. This may not apply to yours.
The skin is supposed to fit very tight though. I've seen so many vehicles on ebay with "new seat covers " in the description. Then wrinkles are seen in the pics which scream lack effort install.
My bucket seat bottoms weren't as hard and the rear seat bottom. I had them upside down on the floor with my 200 lb junior standing on them. For the rear seat bottom I had a piece of 2X6 across the springs with junior and his wife standing on it.
Every life time experienced uphostery man I've met has had his hands messed up bad with artheritis.
Now about those rods in the seats. There should have been 2 hogrings daisychained down to the seat frame. That didn't prevent the rod from traveling lengthwise.
I know one guy who bends a small loop at each end of those rods. A torch is required to bend that stuff. The loops look down , replacing one hogring. This leaves their ends rounded and anchored. Prevents customer comebacks.
Thats all I have to offer. Good luck.