This is a visiting locomotive, all the way from New Mexico!
Purchased on a visitto a model shop in USA, as a "I'll need to buy something having been here so long" kind of thing. It pulls the track cleaning truck, which operates on the same DCC number on loco function F1.
A Digitrax DN135 decoder is fitted. This is slightly larger than most N scale decoders nowadays, but fits easily. It is solvered to the PCB with the wire numbers clearly marked; the decoder fits under the PCB.