port placement??

[cockeyed00]

I have an 02 F250 Crew Cab and built a custom box behind the rear seats. Each chamber is around 1 cu. ft. As of now it is a sealed box but I want to port it. There is only one thing, the box demensions are roughly: 56" wide, 8" deep bottom, 4: deep top, 18" tall. The only location for ports are vertical somewhere on top of the box
box in truck (http://www.ford-trucks.com/user_gallery/displayimage.php?&photoid=23636&width=0)

any suuggestions???
thanks

[InhumanAcura]

There isnt a problem with firing the ports up as you described, but I would recommend more than 1 cube if your going to port it. Check the JL spec out for what would work best as far as volume and port displacment.