Yikes. I hope that is not the case, I don't want to have to remove the head.

Just checked the OVP relay. It looks original, although it is no longer bolted on to anything... just flopping around in the battery try. The fuses are fine, and when I unplug the unit it absolutely will not start, so it seems to be functioning.

Guess I'll go buy a compression tester tomorrow and hope for the best.

edit: relay has the newer part number, so it has been replaced at some point.