Dam, those things run on 2v?
if so, there is NO WAY it will run off the 14.8+v your car runs at. Your best bet is it crack the adaptor open and just crimp onto the wires going to the regulator in the cig plug. There should be short wires for the + center and the - on the side contact inside the thing. Just crimp on to those, run it to a switched out in the fusebox and route the wire. Shouldnt take very long.