Car has been running very well.

Replaced oil and filter then car would not longer start.
Engine does not turn over, had battery tested it was ok.
Replaced starter with anew one.
Checked power to starter, 12Volts to starter ok, measured voltage to sloenoid approx 8v when try to crank
I can hear the starter, but it just clicks
Took a jumper cable & hooked negative lead directly to housing of starter.

Removed starter several times and realigned.
Moved flywheel carefully with a screwdriver moved no problem.

Car is behaving like it has a week battery clicking, when trying to start, had a battery charger on it over night.
Checked and cleaned all leads look ok.

Has me stumped.

Battery cables like to corrode. Check the connections for cleanliness at the battery. I've seen many a Bonneville with power like no other but a no start due to the cables.

Turned out to be a bad battery which would test ok. Replaced battery with a new one car runs great.

Thanks