This loco released by Atlas December 2005. The TCS M1P-15 decoder fits plug n play for this locomotive! Thisdecoder is the TCS M1 with a harness 1 3/4" long. The wires are arranged coming off the NMRA plug to the left. Notice the M1 decoder rest against the loco frame just behind the front truck. The wires coming off the decoder are formed to route them between the connectors on the Atlas light board. They must also be formed as shown to allow clearance for the loco shell to be re installed. M1P-15 MSRP $36.95.
2. Remove the shell by lifting it straight off.
3. Remove shorting plug in the NMRA socket on the locomotive light board.
4. Install the M1P-15 decoder as shown. Bend the wires away from the decoder at a right angle and route them between the connectors on the Atlas light board. Plug the connector into the NMRA socket with the orange lead at pin one position in the socket. Pin one is marked on the the loco lighting board. A dab of RTV can be used if wanted to hold the decoder in place.
5. Re install the shell and couplers and it is finished.