Got some great advice and guidance from Derek and was able to pair my phone WITHOUT a pairing button. It's all pretty simple:
Remove the housing of the 18 pin connector that the pairing button is supposed to plug into. There is an indention that you push down with a thin screwdriver and the housing pops off.
Then locate pins 1 and 17. Again using a thin screwdriver, push down on the exposed metal to push the pins out of the housing. You do not need to puch the pin out through the holes but you could. With very little force with the screw driver and pulling slightly on the wire, the pin will come out of the housing.
Then you have your pairing button. The procedure is simple... hold the two pins together and count to 3 and then turn your ignition to the 1 position and count to three then release the pins. You should see BT pairing on your radio.
After successful pairing, I easily slid the pins back into the housing and stuffed it away.
No pairing button required.
Proud owner of '04 M3 Convertible: