Part throttle bog then backfire?

Vac is hooked up, I will double check that it's the right port. (pretty sure though).

Engine is a 360. I'll pull a plug on wed of it's not pouring rain.

I did adjust the accel pump per the Holley guidelines last night. Didn't work.

Will check floats on wed too. Luckily this carb has a float window so you can adjust it properly with no disassembly