[Dangerous Doug]

The slider on my ERA is only about 1" thick. That'd save you 2". You can find something similar from Summit Racing. If you didn't need a slider, you could do what I'm doing for my passenger seat: construct a seat bracket out of 1" square tube steel. I paint mine tonight, then press in the seat bolts and mount the seat. All you need is a sawzall, Dremel, and a bench-grinder/wire wheel.

Go with a dense foam, thinner padding in your seat to take some more thickness out.

Liposuction your butt. (Sorry, couldn't resist...)

Looked at your car. Bummer, dude, but at least it wasn't terribly destroyed.

DD