I recently purchased a used 36-ton Shay. It was set up for a Soundtraxx DCC card. I don't use DCC so I was able to get everything back to analog except the original PCB for a sound card that resides in the tender is gone. I was able to match the lights up and everything works. I had one wire left over that I am assuming might connect to the contacts for the engine but I don't know how to ground it to complete the connection. Can anyone help?