bachmann EZ RIDERS for stationary operation?

[@55]

hello:
i want to weather a number of engines ho and on30 with the airbrush, wjile the engine is moving in a stationary mosition,Can I use the Bachmann # 42902 set or do I have to use the # 42901 set w/ ball bearings,?
i really dont see the difference in the two for this application . Thanks

[WoundedBear]

The ones with bearings go under the drive wheels.....the ones without go under the rest of the wheels....ie; pony truck, trailing truck and tender.

Sid