Here is the finished tutorial.
Then you show adding the rails user to the sudo file with vi after adding nano.
Also, once you add a user to the wheel group, you should not need to add to the sudo file, isn't that the point of the wheel group?
you are supposed to use visudo to edit that sudoers file.
As far as installing nano twice, I may have missed that and copied it from the original.
I am not sure what the big deal is...