So I got a new 6V battery today and tried starting it. Like the previous owner said it was popping out the carb...even shooting flame. So after confirming firing order, twisting the distributor 90 degrees in either direction and observing change in backfiring I cranked the distributor ~180 degrees and she started right up for the couple seconds a squirt of starting fluid is good for.
After some whoops of joy (that had the folks run out scared I'd hurt myself), and a quick repeat demonstration for them, I added a couple table spoons of gas and a squirt of starting fluid and had her running for a good 30sec. She sounds pretty good (especially considering the distributor is set to a fairly random position) and almost idles on her own.
She'll probably be moving under her own power in a couple of days.
I'm super happy right now. There's no stuck valves or hard problems as far as I can tell... just little goofy stuff like the distributor cap wired backwards.