Ok, got the dizzy swapped over to 18*, warmed up, vac off, 600 rpm (had to tip some throttle in to keep it there) timing set to 10*.
Pretty much same scenario. 1.5 in on the idle speed, 2.5 out on the mix. Still running rich and rough with puffing black smoke.
Low idle, it barely runs, or dies. If I keep a little throttle on to maintain 500-750 rpm, and I turn the mix screw in, it gets a little better, but I can still crank it in all the way and as soon as I'm off throttle, it'll die. Also tried turning it out but it just got a lot rougher like it was flooding.
When I took the carb off and turned the idle speed in till just before the enriching hole, it was right at 1.5 turns in. I made sure of that.