71 340 running bad

Harms does beautiful work. BUT it is possible that the "O" rings may have been distorted or split on the secondary jets when installed.The other thing is the fuel bowls are epoxied and is possible they are leaking.
Both will cause a rich condition. These are just possibilities.
No vacuum ? Double check for vacuum leaks ? Maybe manifold gaskets ? Base gasket ? Is it a stock cast iron manifold ?