If you have a volt meter or test light
Unplug the 2 or 3 wire connector and with key off test green wire to battery positive, should be no volts, unless that green wire has a short to ground somewhere
Turn on key, test green wire to alternators case(ground), should be battery voltage, say 12.5v
Also test Yellow wire next to the green the same way, should also see battery voltage, but key doesn't need to be on, can be but the yellow wire is a live 12v wire 24/7
Check the white wire, if you have one, its a short jumper wire, make sure it is not frayed at a connector
The "alternator" is a separate part from voltage regulator, i.e. they were separate parts from 1984 and back, 1G, using external voltage regulators that use mechanical relays, the advent of "reliable" integrated circuits made internal voltage regulators possible
But they are connected by wires internally or externally
I can't find a diagram for a solid state regulator
And I am not sure why your battery light is doing that on two different alternator
Not needed but you can read it if you want
The way it works is............
An alternator can not generate electricity just by spinning it
It has to have "startup" voltage, that's what the green wire provides, as seen with the above test, green wire has 12v with key on, traveling thru the battery light bulb down the green wire to the voltage regulator
The voltage regulator uses that 12volts to power the brushes on the armature(part that spins)
The armature is a "ground" at that point because its not spinning, so battery light comes on
The 12v causes a magnetic field in the armature coils
When engine is started these magnetic fields spin passed the 3 field coils in the case of the alternator, this generates AC voltage in the field coils
When the alternator starts to generate it own voltage the voltage regulator switches over to internal power, so green wire is not needed, but is now a monitor circuit, i.e. battery light, so has same voltage as alternator is producing
The voltage regulator only sends 9volts to armature to get out 14volts, or 8v to get out 13volts thats how it regulates the AMP/voltage output
The yellow wire is how the voltage regulator "knows" how much voltage it should send to armature
Electricity has whats called an electromotive force, we'll call it Pushback
After engine is started battery was drain so needs a recharge, low Pushback, so voltage regulator turns up AMPs/voltage to 14.5v by sending 9.5v to armature
As the battery gets recharged its Pushback goes up, so voltage regulator reduces voltage at armature to 8.5v so alternator output is now 13.5v
When you turn on Blower to High or head lights on Pushback drops so voltage regulator sends more volts to armature to compensate, so voltage may remain the same, 13.5v, but AMP output has increased because blower and lights are on
When you raise RPMs pushback stays the same but alternator output goes up, so voltage regulator lowers volts going to armature to keep volts and AMPs the same
If your voltage at battery stays above 14volts after 10 minutes or so of running that means battery is close to end of life, it can't be charged fully so low pushback all the time
It could also be a bad voltage regulator, they can "stick" at one voltage to armature, so voltage will go up and down with RPMs, so easy to test for that
And on top of everything else, they now use GROUND to vary armature voltage, but its much easier to understand using 12volts, and its virtually the same