OK, has anyone else here actually replaced their door speakers?
I have and the 6.5"* (in the car now) fit without any modifications whatsoever, they just screwed into the 5.25" mounting holes (with a little help). I can tell you that my passenger side door panel just started to rattle a few days ago, and I'm not sure what it is yet. It might be the speaker (they are kinda crappy) or just something rattling in the door. I'm not sure but I'm going to take it a part and find out this week and I'll get back to you.
As far as 6x9"* in the front that would be f'ing sweet, but like someone said it would just rattle your door panel like crazy.
'88 Formula - 5.0 TPI - 94,000 miles
'93 SLE - 3800 Series I - 175,000 miles
'97 SE - 3800 Series II - 164,000 miles
'02 SLE - 3800 Series II - 81,000 miles