Atlas GP38-2 decoder

[tnhllblly06]

With much trepidation, I finally decided to take the plunge and convert my layout to DCC. I have sent a few locos out for decoder installation, but I would like to try one myself... an EASY one. I recently purchased an Atlas Trainman GP38-2 because of it's "plug-and play" technology.  NOW WHAT?   There is so much information out there, little of which I truly understand, that the more I look at, the more confused I get. Can someone tell me what exactly is the easiest, most basic decoder to "plug" into this engine?  Nine pin...eight pin, harness...no harness...it's all Greek to me.  From what I can figure out, a TCS T-1 would seem to be easy enough, but when I go to the TCS website the "harness" thing gets thrown into the equation...I think!  Please help!  What decoder should I get?