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Being new to DCC I'm seeking some advice. I have two proto (walthers) GP38-2's #920-75008. Both run excellent and are DCC ready but there do not appear to be drop in decoders available for them. The only ones I can find that are suggested are the digitrax dz143 or the dz125. Both of these decoders are the type that have to be wired in. I've installed drop in decoders in three different locos with no trouble but those were easy, I'm hoping that somebody out there can lend some advice on how to install decoders in these loco's. The wiring seems like it would be really straight forward but the contacts to wire to are not so obvious. Like where are the contact for the motor itself? Do I have to disassemble the frame to gain access to that stuff? To wire in the lights will I have to disable the power or remove the LED's from the existing I completly remove the existing board when installing the new decoder (I'm assuming that would be a yes). These are the kind of things I'm hoping to get answers for. If somebody would have a picture of an installed decoder that would be extremly helpful. Below are a couple photo's of the loco I'm working with

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