Many years ago Weaver offered its 2 rail engines with the option for AC TMCC control. I had worked on a friends 2 rail layout and built a system powered by AC and TMCC. Many of the engines we ran were Weaver AC TMCC 2 rail. But he also had a good collection of DC engines, many older. I put in some DPDT double pull double throw switches for power to the different main track loops and yards. I could switch between AC TMCC and DC power. I used a heavy duty TMCC engine control board with the DC engine outputs wired to the track leads. When we wanted to run a DC engine we flipped the switch to DC power. The AC power supply ran to a board mounted TMCC engine control and the DC output leads to the motor instead were wired to the track. Worked well! you could control AC or DC engines from the Lionel TMCC remote. Here are photos of the set up. #11 and #22 were the TMCC address #'s for running DC.
Also on a 3 rail Brass Steam engine I had I wanted it converted to 2 rail. A friend had his specialist friend that did conversions to the change. He cut each metal spoke of the main drivers on one side and glued them back together so insulated. Then changed all the other wheels.
