I didn't actually think there was a voltage regulator, as the unit accepted a straight 12v OK? I stand to be corrected though.
The Garmin cradle came with two bared wires, with an in-line fuse. I dispensed with the fuse and fitted a standard BMW-type accessory-plug, as I understand the sockets are protected by a circuit-breaker. I like to be able to unplug/isolate _all_ accessories just in case the bike's electrics start malfunctioning.
The BMW parts are:
4 x new handlebar-clamp bolts MC32.71.7.652.161 @ £3.62 ea. (!)
and the bracket MC71.60.7.682.427 @ £25.54.
I also bought an isolating audio lead from Autocom to connect the audio, but I'm not sure I'd bother again. I find it very annoying now the novelty's worn off!
All in all very pleased with the setup though, although I have had occasional
loose connections.
The interface between the BMW bracket and Garmin cradle is a "standard" rectangular pattern of 4 holes - I think 1.2" vertically and 1.5" horizontally.
Not sure I should really be praising this setup as RAM are a site sponsor!