Hey guys, I just swapped out my fronts with JL audio coax units and my understanding is they're 6.5". HOWEVER because of the unique design Mazda used in these (tiny Neodymium magnets, interesting basket design) new drivers are NOT drop in replacements... My shop had to use a 1" spacer ring, AND fabricate a new flange for the ring to bolt to (Mazda used a 3 bolt pattern in the OEM speaker frames) The frame of the door can get in the way of the basket on a new driver. Be sure you use a good shop. I'm quite mechanically inclined and even I opted to pay them the $50 install fee ;-)