First off; Your Carb. (one or more) don't require 'pre flling' as; they should stay full, running or not.
Hank's correct, either pump is okay. You'll only need the electric for long-high RPM usage.
If your floats are set right your not going to "wash off" the cylinder walls and only 2 of the 6 idle mixture screws (center) are used anyway. The end ones are closed because 3 Carb. 'set-ups' idle with only one.
Good luck.
