Do you have the numbers matching motor? How complete is it? Maybe it would be good to take a bunch of photos so we can get a good idea of what you have, and the condition of it, and the guys here can offer you some guidance from there. Also, go into more detail on what you want to do with it. Shocks and lowering springs are easy to reverse, so are wheels, or a front air dam. You could easily keep the old parts on a shelf should you ever want to sell it or return it to stock. More permanent modifications, such as weld on coilovers, or fender mirrors, or anything that requires drilling, cutting, or welding is another matter.