The first two photos give information regarding potential electrical shorting issue. Below these photos is PDF viewable file for installation information using a TCS MC2 decoder.
Important note. There is a short circuit on some of these models that will burn up the installed decoder when you turn on the lights. The problem is from the track power pick up located in the floor of the tender making contact with the components located on the bottom of the lighting board. See photo below. The metal tab that the black track power is soldered to, if it is bent upwards will touch the bottom of the circuit board causing the problem. Please make sure that this metal tab is bent away from the board, it should lay flat against the floor of the tender. To test this with an ohm meter measure between between pin 8 (red wire) of the 8 pin NMRA socket and all of the other pins. Particularly check between pin 8 (red) and pin 2 (yellow). There should be no continuity.
Photo below shows metal tab bent upwards which is the cause of the problem.
Photo below demonstrates that metal tab is bent down. It needs to be toward the floor of the tender not sticking up to prevent shorting against the bottom of the light board.