The vacuum advance hose may not even be connected to the correct place. And, this thing has an HEI dist. Was the HEI around in 1970?
I hope I can find my timing light. It's been a while since I needed to use it.
Between the mice and rats chewing wires and all the hacks from previous owners it may take a while to get it running right.
Nothing like having a big rat run across your foot while checking that flat spot off idle.