The three wires coming out of the cab are: common, rear headlight, and cab light (NW2 shown in photo).
Below are the instructions for installing the Soundtraxx Tsunami (first-generation) into this locomotive. The article was written by Bill Clark and made available by Don Thompson.
Tsunami Installation Guide
Provided by Don Thompson, these are the CV settings with which the models were configured:
Tsunami Configuration Variables (CV) Settings
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