Hi
So ?
(1) what is the Compression Now that you made it run ? each cylinder
( This is a Crucial basic test > the car well only run right if you have good ballenced compression . I always do this first before anything elce and yes when they sit that long
its better to run it before testing most often )
(2) With the Motor running Poor or not and the air cleaner top off looking down the Carb
Throats and accelarating the Motor you can see Gas being pulled from the clusters center area of the Carbs . This tells you if Gas is passing through or not .
Accelator Pumps you can check motor off just pumping them but thats not your basic Prob I don't think .
(3) I hope you found and pulled the " emulsion tubes " when you cleaned the carbs / all the jets and such .

Beyond that if the Car is not pouring out huge amounts of smoke and has good compression ( 135 to 150 ballenced ) it should run good unless you have indeed a unfound Vacume Leak .
Easy Test Vacume : Car outside running just run a garden hose slowley about the Motor
advoiding the Spark plugs and Distributor . Intake Manfold / Carbs / Vacume lines Etc.
If you find a leak you shall know it right away as the water flow hits it > You don't need a Huge Water flow for this

Hope this helps sometimes you just have to countinue onward