Howdy, been lurking on here for 2 years now, I'm getting ready to install a 1989 corvette IFS in my 54 1/2 ton 5 window. What I was wondering is if anyone out there has had any dealings with Flat out Engineering or Progressive Automotive. I'm trying to make up my mind who to go with. Also been wondering about motor mounts. Any fed back will be greatly appreciated. Thanks Dean