Finally got my Pioneer AVIC-D3 installed in my H3 this weekend. I had a few lessons learned, but overall, it went well.
I used the Metra GMOS-04 harness. I have the Monsoon system with OnStar, so this seemed logical. The GMOS-04 also provided a few other leads, the speed sensor, reverse sensor and parking brake (even though I chose not to use it). The only problem I had with the harness was using the wrong illumination light. Use the Orange/White wire!
For the mounting kit, I used the American International GMK382 double-DIN kit. I had to cut out the middle bar to allow the AVIC-D3 to fit. A little careful work with a file will make it look it was never there. I still had to remove the tab that supported the stock radio in the rear. I really didn't want to use a saw or grinder in there so I just broke it out using a pair of pliers.
The GPS antenna gave me another challenge. I used a little L brace and mounted it where the factory GPS antenna would go. The magnetic base of the antenna held it firmly on the L brace. Only problem was that it did not get reception there. Thanks to TonyH3, I found the best location is under the plastic runner that runs along the top sides.
As usual. I have taken a few pics and have updated my mod list:
AVIC-D3 Installation Pics