We decided to fool around with the Holley 500 simply because of finding one on the cheap. We did have the Rochester rebuilt, but it still seems to leak a bit around the throttle shaft and base, prompting us to experiment a bit.
Ignition concerns drove the decision to convert to an HEI set-up. Sourced a Buick even-fire HEI from Jeg's along with some generic wires and a bushing adapter as referenced here...
http://www.6066gmcguy.org/hei.htm.
The new set-up dwarfs the old points dist., but it fits. We swapped the old drive gear onto the HEI and....
I know that I'll eventually regret this, but...
I welded the drive gear to the new dist. instead of drilling and roll pinning
It seemed to make enough sense at the time.
The larger cap is a close fit here and there...but will just clear both the firewall and throttle linkage (thought we'd have to remove that).
We may drop the old Rochester back on for a bit and time it... one thing a time!