As someone once told me, changing the trucks is another way to go. I bought a card of 42535 trucks which will convert 12 cars at a time. Take off old trucks, take wheels off them, install wheels onto new trucks, install new trucks. And since they're Bachmann trucks, they go right on with no mods. Of course though, this works most of the time, not always. Some cars (like my Amtrak ones) wont accept the new trucks. But all my freight ones did. And it helps a lot to make a car with Rapido on one end and the new connector on the other end to make a "transition" car so you can run both kinds. It was like 28.00 total on e-bay for the card of trucks.