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