Thanks for the help on how to remove the shell.  Removing the tank revealed the four screws to take off it off.  I did have to remove the front coupler as well.  Appreciate the help.  Grandson will be impressed that Grampa was able to install the decoder, but I'll have to explain to him I learned it from some great folks on the Bachmann Message Board.

My grandson and I have recently become involved with HO Scale and have been using Analog.  I just ordered a DCC Controller and have a HO EMD E7 Diesel which is DCC Ready with an 8 Pin Plug.  I have ordered the decoder to install and have had luck with video's showing the installation.  What I haven't been able to find is anything regarding how to remove the shell.  I'm new to this so have not had any experience in removing the shell.  Any suggestions.  Thanks, PJM