small problem with the holley 350 on my slant 6

For when you get it started, food for thought.

Does it have the float bowl vent baffle installed? Many people don't know than an inline engine produces much different harmonics than a V8 and that can lead to fuel problems in the carburetor. If the float bowl vent baffle is not installed, fuel can be forced into the vent and actually out the top and right into the primaries. This is why a lot of times you see Webers on inline engines. They are actually designed for inline engines, where that Holley 350 was not. Even with the float bowl vent, they can have peculiar running problems that cannot be explained any other way.

Lastly, do not forget to run the THICK (about 1/4") insulating gasket under the carburetor. The intake and carburetor sit right on top of the exhaust manifold and can percolate the fuel pretty easily. It's a common problem.