Bob..... do yourself a favor and make life a little easier.
Install the Trik-L-Start and let your house batteries maintain your chassis batter when you are plugged into shore power or running the genny.
I installed this on my Outlaw and have never had to worry about putting a tender on the chassis battery. When I am plugged into shore power, the chassis battery is being maintained.
And better than that.... after I installed my solar system earlier this summer, I don't even plug into shore power at home and the solar keeps both my house batteries and chassis battery maintained.
The install was super easy and I opted to mount the control unit in the cab so I could see the status lights easily.
https://www.lslproducts.net/TLSPage.html