Currently I'm working a lot in this thread:
MirageCorp Hybrid Datalogger; Rear O2 0 volts; Exhaust rich; RPMs no match logger - "MirageCorp Hybrid Datalogger; Rear O2 0 volts; Exhaust rich; RPMs no match logger"
Still pluggin along, but I only have 3 more days before I move and I will probably cease work on the car tomorrow thereby setting it up for another 1-2 months without final resolution. If I can manage it with time I'm going to replace ALL of the 3 intake manifold plenum gaskets. It is the last vacuum zone I have not hit aside from the vic motor which I suppose shares airspace with the upper plenum since its attached to it.
I'm still thinking there is evidence to a vac leak, but FIAV looks to be functioning normally though if I replace the gaskets on the plenum and determine whether the VIC motor area is leaking (if it shares airspace) then the FIAV will be the only thing left to replace.