There was another thread on this last week some time. The guy cut down the Gen2 seat pan and riveted the IQ seat pan to it, trimmed the foam and re-stretched the stock seat cover over it, then welded up the "legs" for the rear.
Ive done some research because when I found the pics I wanted to do it to my edge chassis sled. It is a dragon FST iq seat. Or at least that is the closest looking OEM seat to what his looks like. Now if I could just find one for myself to do it.