Hotrod,
Following your excellent instructions, I adjusted the regulator to decrease the voltage at the battery (fully charged and receiving less than 10 amps according to the ammeter) from 8.5 down to 7.4 volts.
Thanks to everyone who responded to my questions.
I feel empowered - and lucky to have this bulletin board as a resource.

My dad always told me, "Don't force it, get a bigger hammer".