Well I got it running. I ended up having to reseal the carb to manifold because I had a pretty bad vacuum leak and it would barely idle. Now it idles nice and smooth but I can't get anything tuned. Everything is lean all the time.

The idle mix screws respond well and I can get it to idle right at 14.0 AFR. But I have very bad lean stumble anywhere off idle. I changed the jets from 73s to 70s and then the lean stumble became very apparent. Then I changed the squirter size from 25 to 28 and it helped a little. I have a orange pump cam on position #1 if that helps. Any ideas? I'm probably going to end up playing with jet sizes over the break.

I just don't get why it would go from running really rich with large jets to running really lean and having lean stumble with slightly smaller jets.

69 Buick Special Deluxe. Intercooled Turbo Chevy 250 @ 15psi on a stock long block. It's kinda fast.