There is no easy way to make your car RWD. The Cadillac in the video has to be RWD, and its chassis is probably completely cut up and re-fabbed for a huge exhaust pipe and a large driveshaft. If you put a driveshaft where your exhaust is right now, you wouldn't have any room for exhaust. There'* a ton of fab work to make your engine bay hold a rear wheel drive setup, and your current rear wheel setup would need to be removed entirely and have new mounts for new things welded on. I'm not saying it can't happen, but I am saying there'* nothing to make it easy. In other words, nothing can bolt on to give you rear wheel drive.
What'* holding you back isn't front or rear wheel drive but power. You need more power regardless of which wheels get it. If you're just straight-line racing the 5.3, there'* no need for the handling and burnout advantages of a RWD platform.
94 STEi and 99 SLO