[Just Some Dude]

Hello All, looking for some wiring guidance here.
I recently bought a HO alternator to replace the original alternator that went bad.
The old alternator had 4 wires connected to it from the van.
The new alternator and connector only has 3 wires.
I am wondering if the “extra” wire(the separately connected wire in the middle in the pic below) is a ground and can be wired to the van instead of into the new alternator.
If this is the case, where do I wire the ground to the new alternator(pictured below)

 

[Action]

I am not finding an acceptable wring diagram on the net.
The alternator has an internal regulator. (Ford now calls this a generator or a power generator)
And the ground is based on the alternator case mounting.
The number of wires has to do with charge indication

I will find a diagram at some point

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