Help! Dellorto 45 leaking gas into the intake!

New engine, preparing for break-in. Used carbs.

dual Dellorto 45's.

One throat is puking gas all over the intake, leaks until the float
chamber is half empty. No other throat behaves this way. The
"neighboring" throat in the same carb is fine.

I replaced needle valve with brand new, lowered fuel level, and no
change.

I removed the top, and poured gas in . It started leaking immediately
after reaching what, half way full? ONLY one throat. Engine sitting on
level ground.

Where the hell is this leak coming from? if you know the carb well
enough, you'll know that there is a phillips head plug screw right above
each mixture screw. Removing that revealed the leak came from there, the
passage leading into that cavity from above.

What to do?!?! Need it fixed in less than one week! Before Friday's
cruising night and VW meet!


Jan