I have an 06 Altima and I am about to install the bluetooth adapter and I was wondering if anyone can suggest the best place to hook the battery wire for the bt unit? It has to have constant power right? Also, where is the best Mic location? Thanks in advance!

You can hook it up to the constant power supply for the radio.

As for the mic, it's a pretty sesitive mic, so just about anywhere in front of the driver should be fine. On/in the dash, on the windshield pillar, up in the headliner... I believe the mic is directional, though, so it's gotta be pointed at the driver for best pickup.

Yes, it's directional. I have mine mounted at the headliner at the windshield and it works very well. And like HiFi said, just tap into the power and gnd of the D3 harness. I've got the BT, XM and Steering wheel controls all tapped into that wire and no problems so far.