I'm getting ready to wire a Bachmann decoder to a pair of specially prepared P2K locos. The decoder will collect power from the wheels of both units and will drive the motors of both units. Obviously this means the units will be permanently tethered to each other. The units are a FA-1 with a Bachmann FT-A shell and a FB-1 with an Athearn F7-B shell. I've heard of this being done on a couple other forums. I'm about to put it to the test.