The K1D4 makes this decoder installation a simple Drop-In.
Remove the shell, and the orginal lighting board.
Wrap a bit of kapton tape around the chassie above the decoder to prevent an accidental short.
Slip the K1D4 in just like the original lighting board.
Make sure that the copper strips on the K1D4 are completely covering the motor tabs.
Enjoy the running your locomotive on DCC.