anyone who might be able to shed some wisdom on this one. 1973 case 222, took some readings on my charging system last night, with the engine running about 3/4 throttle reading across the bat and f terminals on the regulator about 8VDC, then i ground the f terminal and read again, this time reading 15.5VDC upwards to 16.3VDC. Not sure what to make of this. the 8VDC reading leads me to believe the start/gen is failing, however withe the added f terminal ground reading close to and sometimes over 16VDC maybe its the regulator? maybe both? Thoughts?