I was able to get the correct key names by looking at the file, /usr/share/X11/xkb/symbols/pc. The key names used in /etc/default/keyboard are on the left side in angle brackets, for example:
key <BKSP> { [ BackSpace, BackSpace ] };
If you want to change out keys at the graphical level but system wide, you can change it in /usr/share/X11/xkb/symbols/pc. (Make sure the file corresponds though to XKBMODEL in /etc/default/keyboard.) Just change out the names you want on the right side. I was thankful for this article. If you want to change it at the system level, in X and in the console, you can change the information in /etc/default/keyboard. Now my /etc/default/keyboard has this line, and I achieved my desired result to assign the BackSpace to my Super_R key.
XKBOPTIONS="caps:swapescape,bksp:norwin"
(The above also includes where I swap Caps_Lock and Escape.)
Update: The above method in changing the /etc/default/keyboard file does not seem to work or at best does not have consistent results. However, changing the /usr/share/X11/xkb/symbols/pc file does work. In my experience, sometimes the key assignment in the latter file works in a console and sometimes not.