I have a 1990 coupe that I want to fit my 6'6' body into. With the seat out I've got enough room, but its hard to drive this way. I've been told to get a 94-96 seat, remove the rear cross bar at the back of the seat, so the seat will go as far back as it can, and make a manual track to lower it to the floor. any ideas, or would a aftermarket seat work better? Any help would be wonderful.

I think you will just have to talk with folks and see. There are some very comfortable lightweight racing seats available that are thin, and which you could therefore mount way on back.