To get the seat out I sanded the lip so I could see the spot welds then used a spot weld drill. The ones I couldn't drill I used a cold chisel.
My body mounts I made where just 4" angle iron 1/4" thick with gussets.
In the first pic you can see the body mounts are about 1/2" below the top of frame and I used s10 bushings. Second pic you can see how the back is on the frame. Hope that helps.
