Well partway through the wiring I decided to fire it up for kick and giggles.
I have a 2 stage power switch installed, so I let the tubes heat for a minute or two before turning the amp on. When I turned the switch to both on, the board I just finished light up, at that point I remember I installed LEDs under the tubes.
So a new symptom to add to the list is LED under board not lighting for the problem board.
Then I broke out my dads DMM, and the VDC between out and ground on the second boards terminal block(the one with working led under the tube) was around 2 mV and still dropping.
So then I measure LED+ to LED- just for fun, on the working board it measures 2.8V, on the problem board it measure around 0.7V.
Pic to come, I promise. Just gotta find the cable to hookup the camera.
By the time I finished typing this, I checked dc offset again, and it had dropped to .5 mV.