The battery and charging issues have now been sorted out!
I ordered and already received the charger that John recommended above as well as the batteries to go with it.
NOW: I am moving on to the next part of the (eventual) transition. I constructed this shelf under the layout that will be the home of my Base3 hopefully later this year. Since I had some Mianne benchwork rails that I couldn’t use (came from my old liftgate prior to downsizing it from a 4’ to a 3’ gate opening), I cut them up and together with some scrap wood and other spare parts put together this shelf.
“Little Stevie” is now partly hidden LOL!
I already also purchased an LCS SER2 and cable to connect to the Base3 and my AMC (Accessory Motor Controller) that I use to control my turntable with Legacy.
With this arrangement, should there be a problem with the Base3 I will be able to easily plug back in the Legacy base and keep trains running no matter what. I even still have a TMCC base and controller if ever needed!
I suppose now I am ready for the Base3, albeit maybe 6 or more months early!