My Point was primarily about selecting the proper electronic pack based on what you are modifying. Unique in this case to Lionel and command for AC motors.
Airwire as has a board for G with a jumper. The board can't take more than 18VDC for the electronic side, but the motor driver can. So if you only need 18V no problem, but for other model where you might want higher voltage for the motor drive, they can use the jumper. For example 2 12V batteries in series give 24V for the motor drive, but you only send one battery 12VDC to the control section.
Pre war AC Standard gauge is obviously a power hog and having the ability to use a system with higher voltage would be best in the initial conversion.
OR, swap in an MTH DC Pittman motor assembly an than you can go with the Cruise CDR. Lots of folks back fit the MTH motors into there Pre War, especially the ones they like to Run. Here is a picture for an electric. G
