So I'm installing a completely new ballast system in my boat with 4 reversible pumps but I have a few questions.

I have (2) 750's for the rears each will have their own pump, a center bag with the vent running to an IBS sharing a single pump, and a bag under the port seat with it's own pump..

My question is vent locations, ie, best location to drill them and since we surf is it advisable to run the vents from the rear bags to the opposite side to avoid any draining issues from the boat being leaned over?

Was thinking for the IBS vent towards the captains console since it'd be easier to access, where the heater is. The rears just on the middle area of the engine compartment.