Just going to drop a quick update here. It hasn't loped once since I started this thread, with how infrequent it is I doubt it's fixed. Only thing I've done thusfar was finally change the PCV valve, which looked factory. The spring seems seized down, at idle it was rattling something aweful. Pulled it off and the weight inside free-falls inside the valve, along with gunk on either side of the valve and the plastic looked nice and baked. Replaced it and the rattle is gone, haven't test-drove it down the road yet. Did a couple WOT pumps in park, at about 5500 RPMs it seems to do a quick hiccup (PCM trying to shutoff fuel?), but kept rising. I let off right before 6k, the top of the tach. I thought these things had rev limiters somewhere... Takes all of 1 second to go from 700RPM to 5800RPM though. Didn't do more than a couple, was wanting to see where the rev limiter kicked in at park, guess there isn't one. Don't want to chance blowing it up. ;p

Seeing as what was on the PCV valve when I pulled it... I'll probably see about gathering things to take the valve covers off and see what lies beneath them. I think it needs new valve cover gaskets anyway, so I have an excuse to check the lifters.