Stock vac spot Shawn , assumed ported. Resistor wire? Where is that little fella at?
Given the issues you mentioned, I think I'd start from scratch if I were in your shoes.
I'd get a timing tape and piston stop and go through the TDC Procedure
to make sure everything lines up for you.
Next would be making sure I had a good, 12V power source to the distributor. I used the large, red wire that originally fed the OEM module. Before you snip anything, make sure that it maintains voltage in both "start" and "run" position from your ignition key. If so, snip it and run it straight over to the distributor. This will ensure that the resistor is out of the loop and you'll be feeding that D.U.I. roughly 13.5 volts when it's running. I'm not sure how yours is wired but my '83 looks like this. If all goes well, you can come back and solder and shrink-tube the connection. The red wire just above the butt connector shot straight down to feed the OEM module.
Lastly, your D.U.I. is set up to run straight manifold vacuum, not ported. Depending on your carb's ported vacuum signal, that may be why you didn't see the results you were hoping for and it could also explain the pinging you heard, aside from the 16* initial advance
Having to pull it down to 6* is an indication that something isn't happy, assuming that the timing indicator is accurate.
Let me know if I can help with anything.