Jerry, thanks for the tip on the oil pump, I'll be sure to pull it apart and clean it. I'm still not sure what caused this, or at least what the first domino in the chain was. I doubt I'll ever know and I'll just have to accept that fact.
Hush, oddly enough there wasn't much debris coming out of the exhaust side, not really sure why. The pipes are now on the spare engine and seem to be working fine with no rattling.
Current plans are to strip it down to the bare bolts and see what is still good and what is total garbage and build a new engine. I've already got a nice looking pair of lower cases courtesy of Soos for a good price, and I have no doubt I'll be getting more parts from him over the coming months.
Brandon