Yep you have to use a hole saw so the speakers can have enough mounting depth. There are indentions on the door panel from the factory that serve as drill guides for the hole saw and mounting screws.
I think im just gonna go ahead and do it. Ill make it a project one night, just wanna know what size speaker i would need, i allready have an aftermarket unit that can support the extra speakers
I have added similar door speakers in my '94 Cutlass Supreme Convertible from a coupe as the convertibles didn't have that option and it made a huge difference.
I realize it's not a G body, but I think you will be very happy with the improvement.
I was able to squeeze 6.5" Diamond Audio speakers in the doors of my GN , took all day to get the holes just right !!!
I put the tweeters in the dash pointing to the center of the windshield.
My car did not have Concert Sound.
No rear speakers, 2 8" old school Nakamichi subs in trunk ....sounds amazing.
I have some kicker 3inch rounders in the front and 2 6×9 polk audios that require a seperate amp and a big ol sub in the trunk. Gotta have my boom boom goin
I think G-Body parts has a repo of the baskets for the doors if it's worth the hassle for you to deal with them. I don't quite remember if they are riveted in or screwed in. I'm sure intercooled 88's can hook you up with some used ones in the parts section here. I put Kicker 5.25" co-ax in mine but had to trim out the backs to fit.
Ill do some measuring but im excited to do this. Make my club on wheels turn into an ampitheater. Cant wait to let everyone at traffic lights endure my country music and rock