I looked, did not find spec for gap.
Try hooking a volt meter in series with one of the connections to the sensor, spin the rear wheels up and see if the voltage signal fluctuates any.
This would test the sensor function. Now if you had a scope, that would be even better.
This circuit has THREE connectors on it, C100, C201, & C307. I would check all three of them and makes sure the signal is passing through them.
Since it has two wires, one is 12v feed and you said it is good, it could be a lost connection on the other wire going back to the ABS module where the signal is broke out via the PCI bus to feed the speed signal to the Body Control module that produces the speed signals for the speedometer, etc...
The ABS module has one ground circuit. It has two 12v feeds via fuses 4 & 25 in the Power Distribution center, make sure both of them are good.
Just a left field thought, is the speed sensor pickup setting dead over the tooth ring? Did changing the carrier move the tooth ring over?
Does the 410 ring gear require a different thickness tone ring?
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