I want to put a pair of Rockford Fosgate FNQ3614's in both the front and rear, but I need 2.6" of room to install. Does anybody know the depth dimensions of the front and rear????

 

You should have no problem. My boston 6.5 Pros needed 2.5" of clearance and fit no problem. I imagine there's 3" total space if not slightly more. The only clearance problem is the corner of the glass when all the way down. I'm going to be removing the door panels again tomorrow so I'll double check the clearance if I remember.

I used the stock speaker mount (had to pysically remove the speaker from it because it's molded to it) and it fit like a champ (this is probably temporary because I think I'm going to play with the direction and imaging if I upgrade to the Boston Reference Z6 speakers). If you need extra room I'm sure you could fab a spacer bracket as well.