Unfortunately I didn't take photos as I went along. I just started building on Wednesday afternoon and kept going. This was a On30, Bachmann Davernport Gas Mechanical.
I made a new cab and added some extra detail for my Gn15 Loco / Layout
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and here is some more detailed shots, like the radiator made entirely from styrene, the air compressor tank made from a white metal casting using guitar strings as piping.
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and one more of the cab view
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I still have some weathering to do and I want to add some more cab detail (perhaps a pepper 7 Gn15 cab kit?) but it is basically finished.