I would suggest replacement of steel door panels with Lexan panels as being adequate for several years of visible locomotive display use. The EMD latches and hinges are available items. A 4X8 sheet of 1/8" Lexan presently runs about $300, one side of an EMD GP locomotive would require 6 or 7 sheets.

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Recently an eBay seller posted an HO scale Alco RS-3 with hood removed and a very convincing 1:87 12-cylinder 244 engine installed. The model looked similar to EL 1042 as shown in the first posting.

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And here is the visible GP35 locomotive EMD displayed at the 1964 Worlds Fair. It was sold to the New York Central after its use as a display. Overland Models built 125 of these in HO scale about 30 years ago. I am looking at one of them as I write this.

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