It was also designed to accept the shorter board type decoders like the Digitrax DN163A4 or the Train Control Systems ASD4. I recently picked up one of these and as most of my other Western Pacific locomotives already had decoders, this one moved to the top of my to do list.
Most of the modifications to the PC board that are needed are on the bottom side and are shown here in this photo.
I had mixed up the white and yellow wires and cut the white wire too short. The bulge is 3/64 heat shrink to cover the splice I made.
The white wire is placed between the leads of the LED to reach the other side of the board.
This Atlas Master Line N scale GP7 locomotive seems to be a big improvement over the GP7's and GP9's that they released starting in 1996. Besides the fact that either a board or wired decoder can be installed without any milling done to the frame, it also seems to be a more finely made mechanism.
This decoder install was the last one done in my old train room. I had been using a spare bedroom in the house for my layouts and all of my model railroad work since 1997. I have recently moved everything into a new room built especially for this purpose which is about twice a large. There will be a new layout under construction and lots of new DCC decoder installations !