I have an older (DC) N Scale Atlas SD-35 from 2000 acquired used that has been on a shelf a very long time. I've been running it tonight and it intermittently stalls on perfect straight track and elsewhere. I've messed around with a ohmeter and I think the problem is the contact strips between the chassis and the trucks are making unreliable contact. I've bent the contact strips so that they apply more pressure to the truck contacts and it's helped. (The newest gen of Atlas SD-35s finds the trucks hardwired to the frame.) Then other times I think that the trucks aren't doing a good job picking up current. If I wanted to open the trucks and clean them, how do I get them apart? I can't see how to unsnap them. I've checked the motor contacts to be sure they're making good contact on the analog circuit board. Is there a known "bad actor" that's often the culprit with this design? I don't blame Atlas, as this unit has probably sat for many years. Thanks y'all!