New bucket seat cover installation advice?

I think E body seats are a bit wide and a tight fit in an A body. As for the covers
you can add new foam or replace sections and re shape it to fit the covers.
It's not difficult
I thought the frames and foam were all the same for 70/71. I guess I will find out.

Once I fit the covers I will see if they are tight or loose. I'm wondering if anyone had to glue an extra layer of 1/4" foam to make them fit better.