Hi Guys..... I'm sorry that I missed this post for the request for the diagram. Here's a quick overview of the 5 pin plug..
What I sent Dan...
Sound Plug diagram
This is what is coming out of the loco to the tender as per his diagram designations:
Pin 1 = Track Power Right (constant to rear outlet)
Pin 2 = Rear Light Common
Pin 3 = Rear Light
Pin 4 = Switched Track Power Right (for soundboard power only)
Pin 5 = Track Power left (to rear outlet and soundboard)