Filling bowls
 

I am going to remove my carb to add a spacer. When I re install the carb, the bowls will be empty, is it necessary to fill through the ventri tubs or can I just crank it? I was reading where it's best to hand fill initially.

I would just crank it for about 10 seconds. Pump the pedal to the floor and try again. Pump should put enough fuel in the bowls to start it after just a couple tries.

They recommended it so as to not put a surge of gas into the bowls - risk damage to the float valve. That's at least how I took it

Crank it.
There's only 4-7 psi output from a mechanical fuel pump...same pressure seen by the float valve every second the engine is running.

After sitting all winter I'm sure the bowls in my carb are dry. I get in, pump the pedal, turn the key. Repeat a few times and it fires up. I've pulled intakes, replaced carbs, etc., same routine and no problems.