Looking for Speaker sizes, install kits and wire harnesses for a 2003 4runner. Anyone have any ideas?????? ANyone have an aftermarket radio in there 2003 4runner yet? Chris

 

I don't know if this will help you, but it might give you some ideas.

I've got a 6-CD JBL system in mine. 10 speakers.

I HATED the front center speaker, so I pulled up the grille (it comes off with no trouble if you pull it straight up), unmounted the speaker and unsoldered the wires to it.

After a little tweaking of the radio treble/bass/fader controls, the stereo sounds much better balanced than it ever did before.

Then I got a flash of inspiration, and ran my Cobra 75 CB radio's external speaker output line to that disconnected speaker in the middle of my dash.

Now I get good stereo sound, and good CB audio from a "hidden" speaker.