Those are neat subs. I tried getting one a while back but never found a place to order them. Good luck on the install. You'll probably have to make a 1.5" baffle (couple pieces of 3/4" MDF sandwiched together) for a free-air install.
I think a pair of ND-804's would sound fantastic in the front doors.... Can they handle mid-range up to 2500Hz or so? Might have to give Solen a call....
