Thanks, maxwell417. I'll look at the bushings when the motor runs again.

Turns out that the key may have slipped out of the camshaft gear which loosened up a bit, causing really bad timing. My shop says the top end will need a new cam shaft, gear, and the little parts in between, but the valves aren't bent.

The shop said it's $400 just for a new shaft from Isuzu, but told me if I find a better source for the parts he'll use it. Also needs the timing gear and key, etc. which can be got used somewhere. Off to the Wire search engine unless one of you guys has a source off the tip of their tongue.