Alan....
I was following you on Facebook yesterday.....
As stated 3 years battery life, although seems short... From my expaerience isn't all that unusual. Dennis Bennet outta S.D. also had one go 14 years... Very unusual to say the least.I got 5 out of my last one, and it surprised me.
Get that new battery in and test with volt meter... Should be at least 13VDC (13.2as Russ indicated)with bike running.
No good voltage, pull stator plug, with bike running, should be 60VAC, test across any 2 of the 3 plugs... And keep testing 2 til you get all 3 phases tested. All 3 have to test good.. no good? It's the stator.... Common on X's that didn't run tune or oilcoolers in a large portion of the bikes early life. VAC good, it's the regulator..
Good luck... and feel free come back if more questions
Bruce