Crutchfield said these would fit Memphis Audio PRX 6902, but the stock bracket was bigger and the holes didn't match up. I'm not sure what to do now. Try other 6x9s or buy an adaptor bracket to fit some 6-1/2s back there.

mac , gotta try see what Crutchfield says on this ,do a callback - they're pretty cool ,won't make you feel like a dumbsh!@tt , I know I certainly could'a sounded like one once or twice on the phone with them

They actually changed their instructions after I left a review that their info was wrong. They posted this now for 6x9 install; and I really don't know what they're talking about.

*To install your new speaker, you'll need to cut off the back of the factory plastic speaker grille.
*Use the factory speaker grilles.
*The bolt pattern of your new speaker will not line up with the factory screw holes. You will need to re-use the factory screws to secure your new speaker by its flange.

mac, WOW , interesting , a STRIKE for Crutchfield ? eh.

Crutchfield has been cool. They just emailed me instructions from their install book. It basically says the holes won't match up with your new 6x9s. Instead, it says position the new speaker so the factory screws will catch on it's bracket. Then just tighten down and it will secure it. I haven't done it yet, but it seem like it will be tight. Then it says you have to trim the plastic grill that sits above the speaker so it won't catch on it after reinstall. I'm going to use some sound dampener around it to further prevent rattles.

In doing the rear speakers, I thought I'd go over the wiring. I haven't found any diagrams or info online that match the wires in my car.

The rear, left speaker has green wire and yellow wire, and the right, rear side has a green wire and blue wire. So, I did the multimeter test I found on youtube, where I put it on dcv 200m, and touch the wires separately with each lead until the negative symbol goes away. Using that, I found both green wires are the positive and the yellow and blue wires are the negative. I don't know if it's right but what I came up with. I hooked them up that way and they sound good. Very loud.

mac , yes it sounds like you got the right "phasing" that is loudest and best sounding with respect with REAR spkrs. BUT the yhave to PHASE BEST with the fronts and IF 'n you wanted to see , if inclined to do so, by NOW reversing BOTH REAR (Y+BL)on ea. Lr + Rr speaker - you may find an ALL AROUND BEST SPACIAL EFFECT (always play a full VARIETY of music) .Where all speakers (front & rear)are "pumping " out in better overall sonic unison ,so to speak , #1 for you the driver or you may want to take into account "best sound" to passenger's or rear seating too.That's taking it kinda "Far-OUT" I know ,and I think you probably got it pretty good enough to "NOT FIX-what's NOT BROKE"

The multimeter test I was using was not correct.

The rear, left: the yellow + and green -
The other side: green + and blue -