I posted some info in the dash kit thread...

But something I neglected to mention, is that I'm not 100% sure:
a) That the NAV uses the same metal side brackets that the non-nav uses.
b) That the NAV has truly standard double-din screw locations.

Does your double-din DVD have side screw holes in the same location as the 6cd changer you pulled out? If so, I think it would sit too low to line up with the hole in the dash. So maybe the NAV unit comes with different brackets, or maybe it has non-standard holes to screw into. You could probably just drill the brackets you have though.
I know my single-din head is screwed in to the brackets using the higher of the two sets of screws (screws are dead center vertically on the head unit)- and I expect it to be below center on the NAV hole. So how would that work with a double DIN?

BTW, my new amp finally arrived, and I put it in tonight. Everything is done except for this dash peice and putting fans on the amp enclosure. It sounds GREAT though.... I'm very pleased with the results - even if it won't be super styling show quality.

 

i dont have a 6 disk changer its just the regular LS dash. i havent pulled the stereo surround off to check yet, but i would assume that it will line up.