GMC TBI pressure on adjustable reg
I've got a slightly modified GMC 94 1/2 ton, 350 TBI motor, Thorley headers, K&N, off-road Hypertech chip (stage 2), TBI spacer, really free-flowing exhaust, 165 degree thermostat, timing is 4 degrees before TDC, and it runs high octane because of the lean problem caused by the previous owner's 305 injectors still in place. (I've been informed the injectors are not a problem when the pressure is turned up).
I was wondering if any one has knowledge about how much pressure to turn up the adjustable fuel pressure regulator. I've already ordered the part from Summit. (I've been told to up it a lb or two, but is there a way to mount a guage on a TBI? It doesn't appear so from the manual, so how do you go about getting it dialed in to the correct pressure? I'm sure I need to set it back to 0 degrees TDC and then turn the pressure up).
Thanks for the info.