|3D drawings of resistor bank and brake cylinder scaled for H0 resin printing|
Also, the old traction model pioneers like Fritz Hardendorf were not always so exact when drawing underbody parts. Looking after your old Suydam models is not helping too : resistor banks of Sudam models are clearly oversized, as an example
So you need to search other sources. The Council of Tramway Museums of Australasia has probably the best technical online library http://www.cotma.net.au/library/ in the folder "Westinghouse" or "General Electric" you can find some rare pearls.