While I'm not familiar with that specific model, most vintage brass trolley cars had a flat sheet chassis held into the body by screws. I would look underneath for (in the case of a Birney) 4 screws at the edges of the chassis. remove them carefully, and, equally carefully, lift the body off the chassis. Check for any wiring to the pole.
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Gary M. Collins gmcrailgNOSPAM@gmail.com
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"Common Sense, Ain't!" -- G. M. Collins
http://fhn.site90.net
i recently unearthed (during a house move) an old brass-import birney which i'd bought many years ago. i've lost the instruction sheet, if ever there was one, and now i can't figure out how to disassemble it to lubricate the motor or gears. the little critter is free of tarnish as we live in canada's only desert - no humidity, but that means all the bearings are dry, too. i'm afraid to test-run it before lubrication. anyone have any ideas? or maybe an exploded diagram? -arturo