"
With the air filter removed, and the car not running, the throat of the carb intake is pooling with fuel. I believe my GAV is fully closed so I assume the needle isn't seating fully."
The GAV needle won't cause fuel to leak out of the carb, a non sealing GAV needle will cause rich running but will not cause fuel to pool in the throat of the carb.
Your problem is number 1,2,3,4,5,6,7,8,9,10 on the list below you'll probably find it's 1 or 2 if it's been OK up til now
Problem: Remedy
1 Leaking/loose float valve gasket: Tighten/reseal/replace
2 Leaking float valve: (or crud stopping it sealing)Replace ( or clean up if possible )
3 Friction on float hinge: Loosen
4 Incorrectly set fuel level: Re-set
5 Hole in float: Repair or replace
6 Too many gaskets on main jet Check
7 Cap jet or main jet too short: Replace
8 Leaking/loose gasket at main jet: Tighten/reseal/ replace
9 Leaking /loose gasket at cap jet: Tighten/replace
10 Leaking or loose GAV housing threads: Tighten/ reseal/ replace
11 Leak at fuel inlet union: Tighten/reseal/replace
12 Loose/leaking gasket at strainer: Tighten/reseal/replace
13 Loose/leaking gasket at drain plug: Tighten/reseal/replace
14 Cracked housing/leaking passage plugs: Repair or replace