Thanks guys, I have already identified it, it is a 231. The kid was 16; since I posted this last night I have had a chance to interview him personally. Apparently the rear driveshaft did NOT come out. In fact, it was still in place (attached to the rearend) when his dad came and got it off the side of the road. From what I can tell, based on his description of events, the chain inside the case must have jumped and busted the case housing (first), then he said it drove for about a mile before it started getting really noisy and went out with a fantastic bang. There will be no upgrades...they'll be doing good to be able to afford to get it back together stock, with used parts. The transmission was not damaged at all, as far as I can tell. The rear driveshaft seems to be ok, but the front one might need to be replaced. It also took out the brake line that runs to the rear axle, damaged the fuel lines and destroyed the main wiring harness...even caused damage to that clear up in the engine bay. It will be expensive to fix. I'm wondering if I can buy just the dual u-joint knuckle that goes on the front driveshaft? That piece is wore SLAP out.