Some personal notes after my own installation: First, thanks to AGS for the original post. Without his mirror housing and wiring harness pin identification information, this would have been something I wouldn't have tackled myself.
Second, despite what another member said earlier, go ahead and remove all three mirror housing pieces. While you may be able to separate and remove the mirror wiring harness by only removing the largest and first piece, re-mounting the harness with your newly attached cord for your radar detector without having access to the back of the car's harness for support is nearly impossible without removing pieces 2 and 3.
Third, when the Blendmount harness leads are inserted into the car's mirror power harness, they don't fit snugly, so use electrical tape to firmly attach the braided Blendmount radar power wire to the car's existing mirror wiring bunch. Also, I found it useful to feed the end of the Blendmount harness through the vent slats in piece 1 of the mirror housing
before making electrical connections. The slats provide a perfect opening to feed the wire to your radar detector without having to drill into the mirror pieces.
Reassembly of the three plastic pieces was easy for the two small pieces but more difficult for the first and largest piece removed; there are two tabs on the side that must be aligned perfectly to make it close back up.
The whole installation took me about 45 minutes, but that's including futzing with the wiring harness connector before I said fugit and removed the other two trim pieces. Save yourself some time and take all three pieces off. It looks great- no meandering wires across the windshield top, and no fuse box patching.
