Well as an update I took my PCVs off and cleaned them thoroughly with carb cleaner. The Passenger side one had a lot of 'bits' come out of it, but it didnt discolour the carb cleaner barely at all. It also sounded mostly clean when I removed it. The Driver side was another story, it was gummy inside, the piston would barely move when I shook it. Dumped it in the bucket of fresh carb cleaner and it all turned brown, dirty brown and three times as much bits came out of that PCV. Good lord that driver side PCV was a pain to get out and back in, took me like 30 minutes just for that one, took me 5 for the passenger.
Drove the Z around, noticed an almost immediate improvement in oil pressure, at idle it hovered around 40psi, maybe a little lower and sometimes higher, but not within worrying levels. Oil pressure did increase correctly with throttle. I went wide open to 80mph and the oil pressure did pick up, although it never went past 55psi, so I'm about 1/2 quart low.
I still have the missfire/hesitation, I think that will go away once the oil finally burns out of the chambers. I drove to work which is 2.5 miles away and went up to 80mph. When I pulled up and stopped my car the smell was terrible. I drove back home another 2.5 miles away, oil pressure improved again along the way, and when I parked it at home I smelt NO burning oil from the exhaust. So that made me feel a lot better, all from a stupid pressure valve. So I guess next I need to do a complete oil change and stick with conventional for the time being, might go back to synthetic later.
While I was at it I removed my cruise control module and cable, my 90 chassis lacks the hardware for it in the car, so no point in keeping the mechanical stuff.
Found another fuel leak, this time again from under the throttle cable, I had already fixed that line a few weeks back. It is very mild though, car sat for two days and it was there, drove around and it went away. Ya I know bad, but I can't access the clamp facing the driver side, it's tilted too far back the wrong direction.