That rocks! With a few minor upgrades, that'll be a really fun ride. The cool thing with a bike like that is that it will be totally appropriate to build it out with a mishmash of parts. I recently saw a bike in similar condition and the owner had simply stripped the parts off the frame and fork, then scrubbed the dirt off and sprayed about 4 coats of clearcoat on there to prevent any further rust. He had some pretty nice mid-90s Shimano parts on it. Talk about embracing the ratty look, that guy owned it. Good luck and great find!