im more curious about the front. the black mesh they use for these speakers is made to allow the sound through, id be worried that guest or others may hear the sound of my fans humming inside from the front. but i suppose a piece of cardboard or plywood would stop this. im not sure ill go the same route you went with ventilation i might only use one fan, but im not positive that will cool the box off enough, im concerned about stealth for the moment, so if i can use as little openings as possible im going to take the route. im thinking i might intergrade the front to look like its never been modified. might even have a fake woofer cone put over the front, then ill make the back pretty much just a door. not positive yet. im also thinking of have a small carbon filter box inside, but i again dont know how necessary this will be. the box will be in a room with several aquariums so its always smelling 'funky' in here
EDIT: maybe blacked out pieces of pvc pipe around the intake and outtake? would allow for more control over air flow along with eliminating more light