I believe it is only necessary to change the copy in your user directory.
Master.ins is not really how Cakewalk implements drum maps. This is primarily intended as an interface to hardware instruments. This is why the names may look a little odd. They all relate to some piece of hardware. It is possible to extend Master.ins and it can be used to contain information about softsynths.
You can edit Master.ins to suit your needs. The only sections which matter to the note names dialog are the ".Note Names" section and the ".instrument Definitions" section below it. The names do not have to be numbered, you can create a named section called
[Session Drummer 2] if you wish. The key is having the notes defined in the ".Note Names" section and a corresponding section in the ".Instrument Definitions"
For example if there was a ."Note Names" section which looked like this
There should be an ".Instrument Definitions" section which looks like this
FYI, I did not create a Session Drummer 2 section. I renamed an existing section to serve as an example for the image.
I think you will find the "General MIDI Drums" is pretty close to what you want. There are some extra notes mapped in the octave below the kick to trigger the patterns in SD2 and some minor instrument changes. They are all documented in the SD2 help file.
good luck