For now, just replacing the "headunit", I'm ok with how the speakers sound. I have a Droid, and I've been using a set of PC speakers with a small sub stuffed behind the seat, but it's a little messy. Any receiver with a line-in would work but bluetooth would be ideal.
Crutchfield tells me the following:
Factory replacement info:
In-dash stereo
6.775" depth; Size code E,M1,S
Front speakers
Front Door: 6-1/2"
Far rear speakers
Behind Seat: 6x8"
E - "Euro-DIN" stereos attach from the front through the 2" tall rectangular hole in the dash, sliding into a metal sleeve that attaches to the front of the dash.
F2/F3/M1 receivers are designed as direct replacements for certain Ford/Mercury factory radios. You won't need an installation kit.
S - Similar to "U" chassis, but with a taller nosepiece or offset shafts. They fit the 3-hole dash opening in many older vehicles.
The toolkit recommends these:
http://www.crutchfield.com/p_1208656...air.html?ssi=0
http://www.crutchfield.com/p_1207050...ess.html?ssi=0
http://www.crutchfield.com/p_1203055...Kit.html?ssi=0
I'm not sure if I'll need the in-dash kit, it looks like the stock radio already has the plastic piece at least, but it's cheap enough I may as well get it.
A quick google search didn't reveal much about the stock speakers, but I'm guessing they probably require very little power.
I'm not sure how to tell if a receiver will fit, are they all a standard size, and will fit with that kit that crutchfield recommends?
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#1 seller on Amazon:
http://www.amazon.com/Pioneer-DEH-13...9846497&sr=1-1
-200w output, aux in
Would work, but I don't feel the need to have a CD player, no BT but the price is right
Cheapish unit that has bluetooth and good reviews:
http://www.amazon.com/Boss-755DBI-Re...9847438&sr=1-1
-320w, aux + BT
Mixed reviews, doesn't say explicitly that it supports A2DP streaming
Thoughts?