Cranks but won't start. Unplug ground at field spade on Alternator and it starts?

Took new alternator off. 6 ohms spade to spade. Each spade is open circuit to alternator housing.

Swapped old alternator back on no difference. Old alternator is a known working unit.

Bought new battery at rest 12.5 volts. During crank 11 volts. Car starts if I unplug Ignition 1 from voltage regulator. Voltage regulator hooked up sounds like no spark engine just spins.

Start engine hook voltage regulator to Ignition 1 amp meter shows charging even with lights on. Let it run amp meter shows reduced charging. Does not discharge lights on.

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