truck enclosure

Need some assistance from the pros; I've done plenty of boxes in the past but never the actual design. I'm using the subbox pro website to create a small ported box for my R1T. As I'm designing the box, I'm trying to make sure this will work, as the negative offset of the sub has me questioning...

(New to audio stuff) Currently have: Blaupunkt 3000w mono Kicker CompC 44TCWC104 (preinstalled 10" in a 0.66cf box, ported) ~$240 all in and I can feel good bass, just wanting to go bigger My buddy has this same sub and same amp just double the size of a ported box in a SUV and his rattles hairs...