Holley 4150 dripping fuel from primary discharge nozzle?

Look at the bottom of the throttle plates, bottom of carb,
you will see a slot it should only show around .040 or be shaped like a square or just slightly rectangle. If it's a longer rectangle shorten it to square. Before you instal the carb blow it out with cleaner every hole in the metering block, take out your A/F screws and spray those, and also the 4 small air bleeds you see when you look down the primary side of the carb by where your boosters were leaking, they will be towards the front of the carb just above the boosters.
As for timing if it's a mild motor with small cam set it at 12 to 15 initial, if a bigger choppy cam go 15 to 20 for starters.