Yup, speedo is all thru the trans and PCM.
ABS reluctor is just for the ABS, but the gear sets are different for an ABS equipped car.
There is a portion of the pinion gear that is thicker to retain the ABS reluctor.
You can use a regular gear set, without the reluctor, but you won't have any ABS, and the light will be on as soon as you roll, from lack of wheel speed input.
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