Congratulations to you Gretsch929.
I will get back to try to explain how the Mono, and the ROS (stereo Jack) work,,,,,,,but I'm heading out and will definitely get back to you. Others may wish to explain it for you in the interim.
But here's a good idea for you as you are new to this guitar and are not sure how the inputs works. In the service tab at the top of the page there is a copy of the manual have a look at it
Also do a forum search ( type in ROS) read what you can, and gather some info just to acquaint yourself with how the system works. It will give you a head start! It will make explaining it a lot easier if you do some reading first!
There is a fair amount of info you will find under (ROS) It may answer some of you questions. When I return I shall endeavour to explain how the stereo function works.
You need 2 amps and some special Stereo cables to use the ROS input on your guitar)