Pics show batteries after I returned from getting 2016 G23 winterized. Guy told me to leave negative cables disconnected and not hooked up to the onboard charger. (His advice: reconnect in Spring and charge for a few days. Good to go.) You can see in pic showing both batteries that they completely disconnected cables on left battery; on the right they disconnected two and left a third on the post with the nut just put back on loose.
I plan on reconnecting and once a month or so over the winter and charging with the onboard charger for about 48 hours; and then disconnecting again.
Want to know best way to proceed.
TIA
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