The cell phone is a Motorola StarTAC ST7760 digital phone, mounted to a modified "Navigator" hands-free kit.  The Navigator (bought from pluscellular.com) is designed to be plugged directly into a cigarette lighter, as shown.  I sawed off the cigarette lighter plug, and wired in a power jack from Radio Shack (useless for now; note earlier issue with ground loops & Autocom).  The great thing about this mount is that the phone is securely held by a clip at the top - it's not going ANYWHERE.  I fashioned a Rube Goldberg-esque bracket to mount it to the shelf; I won't embarrass myself by showing it in any detail.  I may be able to tap into the mic/speaker circuit of the Navigator to improve audio volume through the Eurocom, but that's probably a winter project.  I did manage to fashion a bracket that allows me to remove the Navigator during wet weather, since it's far from waterproof.