Rear Seat Foam Options?? Build from scratch, cut/replace sections of original??

[Maximus]

Hey guys,
What did you do with your rear seat foam?
I have a couple of front-to-back tears on the bottom, and they made some nasty tear openings in the foam. I was thinking about cutting them out in some sort of logical "butt area" shape, and make a equal trim on the other side, and infill with a dense upholstery foam. Don't have a clue if this is the best route?? I have a new replacement seat cover in the box, so the upholstery i am okay with, just the rebuilding of the foam.

I also looked at getting a 73-up seat for the foam and trimming it down to fit the round curves. I also heard of people cutting down a front bench seat foam down to size...

What have you guys done? photos would also be a plus...