Precision scale brass tender trucks

[nkalanaga]

And, if your model is real old-school, with a brass frame, make sure all of the insulated wheels in both trucks are on the same side, or you'll have a short through the frame.  Beyond that, you might need to use an insulated drawbar, if the loco frame is also "hot".

[brill27mcb]

Boy, weren't they the good old days? And these brass parts and kits were considered an upgrade to the quality of your model...   

Rich K.

[nkalanaga]

50+ years ago, they were an upgrade.  There wasn't nearly the variety of high-quality plastic stuff, and 3D-printing was unheard of.   Today, not so much, although they can still be an advantage, if one wants more weight in a model.