After using the other style with the 1” holes and rubber flaps I think it really comes down to fans and biggest most powerful fans that with fit. If the fans move enough air there should be no issue with air flow, at least that’s my idea. Like said earlier, if this set up doesn’t work I’m done spending money on it. Flex fan with Milodon hp pump and a shroud over cools this 511 filled with hard block.