I found a 60/40 seat at a pick and pull today. 99 Suburban was the donor. I have the old seat frame removed less the back cross piece. I’m considering taking an 1/8 inch thick sheet of metal and running it from door to door starting where the original seat frame was welded and back to the wall of the rear seat frame. I hope I’m describing accurately. It would smooth that floor out and make it easier (in my mind anyway)to mount seats. I saw one similar in a youtube video. If anyone has experience I’d love feedback or suggestions. They sit nice just mocked up. I’m getting a couple extra inches at least. I need it. lol.