Fellow 2 railers, despair not. I was one of the (apparently) inadequate numberof people who ordered the CNJ first time around in 2 rail, but was rebuked by MTH,
You have two options
1) Buy a 2 rail Train Master. (They appear on eBay every so often.) Try to buy a roadname that is not in this latest run. Buy this new offering in CNJ. Swap the shells, but keep the handrails from the 2 rail model. Paint the handrails, pilot, and pilot spacer the right colors (TrueColor makes the right Sea Foam Green). Then sell the CNJ Chassis with the original 2 rail roadname shell on. It will sell easily, as its got PS 3, and is not in this latest run. This is the path I am taking.
2) Every MTH product I have seen that originally had the PS 2-3 switchable trucks has them even in susequent offerings in 3 rail only. I don't know for sure about these, but its unlikely MTH (or whoever is making them now) will have invested in new tooling. So you can simply swap the 3 rail wheelsets for 2 rail wheels. Add your own pickups, connect one side to chassis ground, the other to the center roller post. The pickups may even be there. Fabricate a new pilot spacer. Its a simple piece of 1/8" Styrene. Paint the edge the color of the pilot. Then redo the handrails so they go down the steps. That last part is the only one that is challenging. But its doable.