Great looking box, and those subs look really nice in it. I hope you have a REALLY dark tint //content.invisioncic.com/y282845/emoticons/satan.gif.9c6a335ed7aeeed3ee273e573f1fcaac.gif
I think 6" is just enough clearance. If you don't have enough room it can effectively lengthen the port and lower tuning.