I think the PCC was an attempt to make a trolley look like a bus, as if that was an improvement.  LOL.
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Sid's right--look at some of the GM buses (TDH-45 comes to mind for some reason) from that era and the similarities are obvious: the odd-shaped front windows, paired sliding (I hope) windows in the passenger area, and the sloping roofline, to name three.
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