That one's going to be a hard-wire install. It's been a decade or so since I opened one up, but I seem to remember it had a single light bulb, and was non-directional. If that's the case, you may be able to use one of the Digitrax Athearn decoders, it has all the little clips already soldered in place, you just replace the old ones with the new assembly. It's a DH163AT
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