I discovered that I didn't understand the various inconsistent and confusing wiring diagrams for the TACH signal.
Once I figured my error, I re-wired the VR, it and tested it still running the Q-jet. Good solid signal! So....
I did it again.
Swapped the Q-Jet out for the TBI, and it fired right up and ran like a charm. A bit rich, though, but ran well.
Tomorrow I'll calibrate and install the new wide-band, and start tuning it.
I'm excited. I am so fraking done with carbs.