Huzzah!
The IDE gave me the option of COM 1 or 7, and 7 did the trick. Tested it out on the ride to work this morning and it worked without fail, even on dumpy pot-hole covered roads!
One strange thing I've noticed about it: the speed is pretty spot on between ~20 & 40 MPH, but is 3ish MPH high at 55 and 7ish MPH high at 60.
