There shouldn't be a any fuel coming out of the boosters at idle. Air flowing through the venturi should be the only thing that draws fuel out from the boosters. That is a sign of too high a float level, dirt in the needle/seat hanging them open, defective needle/seat or excessive fuel pressure forcing fuel past the needle/seat.
Looks like you may have found your problem...or at least one of them!!!
When you work on Spaceships for a living, how bad can a workday be?