Most 1904 carburetor these days have warped bodies where the float bowl attaches. The biggest problem with the fit of the 1904 float bowl is not the bowl itself. Rather, it is the presence of so much warpage in the main body surface to which the bowl mounts. I know of no other way to fix this than the way that I use: put the main body in a press, heat it up and press straight the “ears” to which the bowl mounts. Yes, after I get it as straight as it is going to be I dress the gasket with some Permatex Anaerobic Gasket Maker, but that will do you little good without a reasonable straight main body.
This is an extremem example of a warped Holley 1904 bowl, but it did come directly from a customer so it does happen. This bowl has had the screws overtightened repeatedly over the years causing the ears on the carb body to bow out.