design choosing colors

i am near finishing a subwoofer encolsure and am looking to paint it.... i drive a jeep grand cherokee that is forest green and flat grey.  the interior is a dark gray and black cloth.  i am going to repaint some of the dash and door panel details to match (mostly because i think the fake wood grain on the dash is ugly and becuase i want the sub encolusre to match something.) originaly i was going to match the exterior of the jeep but idk any more.

if anyone can think of any neat color sceme ideas of the top of their head it would be a big help....

also, if there are any general rules to follow in picking colors that would help (i.e never go darker, or never go lighter).  something to point me in the right direction

I would look into the "Rules of the Color Wheel". But since you are planning on doing some of the interior panels to match the exterior, then I would carry the same effect to the enclosure as well.

Personally, I would stick to a paint scheme that would compliment either the exterior or interior specifically. I would go with a Forest Green Base coat with a Flat Gray trim. I would also consider drop shadows at the transitions with a black pinstripe to help separate them and clean up the edges. Design would vary based on the construction and fundamental design of the enclosure in comparison to the box itself.

Pictures to help us help you please.

Ganbatte ne!