i would do like adam said but upgrade some things. It would be awesome to be able to put an LSx t56 combo in it. Or the Lq9-t56 combo. You can get those for a decent price these days and still have an almost worry free setup.
On the body side I would get the rust fixed (easy) and do something that makes you happy. Like bag it or lower it some. I like to see older trucks modded (not just engine, all over) and wouldnt mind seeing that beast either.
Also do you still have that number I PMed you a while ago for the body work? If it was you I PMed.