Installing a new Delphi stereo in your truck is pretty easy, but figuring out where to connect the bluetooth mic is enough to make a person crazy. Get it wrong and you risk damaging the stereo and mic. The BT mic connector looks like this 
The wire on the mic is about 12-feet long. To begin installation you first must decide where is the best location for the mic based on your driving and posture habits. The mic should be facing away from (or at least not directly toward) the driver-side window to avoid picking up wind and road noise. Secondly the slotted openings on the mic should be visible to the driver while seated in the truck.
Now that you’ve decided on the best location, it’s time to route that 12-feet of wire. Newer trucks with more cosmetic trim can add a level of complexity, but take your time to ensure the bluetooth mic wiring will not come into contact with any moving or mechanical parts. Also be careful to not crimp, crease or fold the wiring as this may cause minor defects in the inner copper strands which can lead to diminished voice audio quality.
Once wire routing is complete there will likely be at least a few feet of “extra” microphone wire. This excess of wire should be carefully and neatly wound into a small hoop which can be secured using zip type cable ties, electrical tape or even twist ties. Make sure to leave enough free to reach the back of the stereo.
Looking at the back of a Delphi DEA500 series stereo you will notice the wiring connector is located on the right hand side of the stereo, but where to plug the wiring harness in can be a little confusing as the pins and sockets are not labeled. 
Here you can see the placement of the truck wiring harness and the bluetooth mic connector placement. Keep in mind that each of these connectors will have a snug fit, but should not require much force to make the connection. While the wiring harness or harness adapter in your truck may not use the same color wires, if your truck harness connector is of the ISO-DIN type (most newer trucks are) the connector will be the same shape and size and will plug into the delphi stereo as shown here. The bluetooth mic connector will plug into the top right-most location.
No microphone pairing is required. Your cellphone will however need to be digitally paired to the stereo. So once the wires are connected you can slide the stereo into the metal “cage” and power the unit on. Simply follow the instructions in the owner manual to pair your bluetooth capable cellphone. You can now place and receive calls through the stereo!