I still have an '86 GT I bought new, but it was a daily driver and didn't get the best of care. In the last couple of years I've added rear discs, an '87-up front
suspension, new bushings, springs, shocks, struts and added aluminum heads, E-cam, Edelbrock intake, headers, etc. It still looks pretty original, and runs good, but not as smooth as it was stock. I still have most of the stock stuff and can return it to mostly stock/original if needed. I see so many original Fox-body cars that have been cut up/torn up/messed up/"customized", etc. that if I wanted to make any substantial modifications I'd look for one someone has already messed up.