And as the OP said he tried 2 Holleys and 1 Edelbrock. The Edelbrock doesn't have a power valve to blow out. If fuel dribbles out of those it would probably out of the bowl vents because of a needle/seat/float or float adjustment issue. To
@71_dart_swinger , did you by chance change the fuel pump? Excessive fuel pressure will cause a rich run issue. You don't need any more than 5#.
