its a white wire on the harness in the car, and a blue wire on the crutchfield harness that plugs into your car's harness. then there is the wire that comes out of your head unit which is probably gonna be blue as well, but there is no real standard here.. most harnesses you buy have a blue wire that is there for a power antenna. you can pretty much use any 12V source to that pin. that pin being the white wire in this picture.

Thanks for the clairification guys!

Purduealum, see ya at the meet on Friday.  If you don't mind at the meet, I'd love a tour of the mods you've done so far.

hey guys - i'm getting ready to pry out the trim to install a stereo.  i'm most concerned with what to use to pry out the trim.  how careful should i be?  i've seen the pics of installing a stereo, but i'm still scared that i'm either going to break or scratch the trim with a flat head that i plan to use to pry it out.  can i just pull it out with my fingers instead of a tool?  any pointers would be helpful.  thanks in advance. . . 

cool thanks for the advice - what i did was i wrapped the screwdriver with electical tape.  it worked well, almost too well since the entire trim flew straight out and hit the ceiling of the cabin as a pried with the tool.  i should've been ready for that.  luckily nothing got damaged or scuffed.  it took me about 20min. to get the stereo in.

This thread deserves a bump for excellent instructions and pictures.  I tried searching everywhere on Nasioc and Scoobymods for a writeup on installing the Forester din pocket, but no instructions were this detailed.  Made installing the din pocket and deck easy.

Great write up and pics, but don't use 16 ga wire nuts... Soldering in the stereo adapter harness to the aftermarket stereo harness is so easy and so much better.