Can't Get My 65' 122s Started

I am having a hard time getting my 1965 Volvo 122s back to life. I have rebuilt the dual SU HS6 carbs, rebuilt distributor, timing is initially set at 20 BTDC, new fuel pump and filter, points, head gasket.
Any suggestions on a good starting point for setting the carbs (jets, idle adjusting screws…). The float bowls are filling up and it appears that gas is getting into the carbs.