Still hesitates off throttle...

Hello, I have searched and tried just about everything I have found. 225 slant six with the holly. Accelerator pump seems to be working and rebuilt the distributor. The problem seems to be the vacuum advance. Timing goes from 5 btdc to about 22 degrees with the vac advance disconnected and just running the mech advance. Connecting the vac advance, the timing shoots to like 15 deg Before tdc. According to the haynes manual and the OG dodge manual everything is correct. Honestly stumped. Runs pretty well with the vac advance plugged. Falls on it's face with vac advance hooked up.