SINCE ALL THE WIRES IN A STANDARD BACHMANN DIESEL ARE THE SAME COLOR HOW DO YOU HARDWIRE A BACHMANN DECODER INTO A NO DCC READY LOCO? THE DECODER HAS COLORED WIRES & THE ENGINE HAS ONLY RED & BLACK. DO YOU REMOVE THE BOARD IN THE ENGINE NOW? ENGINE'S IN QUESTION ARE GP 40 & GP38 NOT DCC READY.