With just a little bit of trimming, and some new wooden baffles i got a Pionner 6.5" mid-bass driver into the front door. My '98 had 5.25" from the factory. I can't remember now, but the baffles i built were about 1.25" thick. I took the pocket off temperarily to be sure they were mounted in the right spot, the removed the door panel and re-attached the pocket. I replaced the factory tweeter with some carbon dome pioneer tweeters, to some slight trimming of the dash with a dremel and flexible shaft. In case anyone questions my brand choice I have them left over from when i worked for Pioneer, loved them and will keep them until i kill them, but they've lasted thru 4 vehicles, and 12 years so far. And as much as this pains me as a former pioneer employee i am still using the factory alpine built unit, but had one of my friends who services all brands of mobile electronics wire in a set of RCA's in the pre-amp stage bypassing the internal amp, sounds as good as anything alpine has ever built, except for the old 7909 (we'll see if anyone recognizes this model, as it is more than 10 years old, but still a common competition piece, and infact alpine re-released the mode about 7 years ago for a higher price than when new) I do need to get my Pioneer/Premier unit back from my Brother as well as my 50 disc changer soon.