Hollowing out the Cooling Ducts

I won't be putting too much CAD work into the ducts yet until I can do a water ripple test. Basically I place a small cup of water under the nozzle and check the pattern of the ripples with different air flows. Later on I can do some fancy air flow simulations but frankly it is really difficult to go wrong with two large blower fans when compared to most chinese printers with half size blower fans or no blower fans at all.

Cheers!