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The OE 993 units IIRC have plastic bodies vs the older metal 964 ones. I have 2 sets of 964 fronts left over. The only primary difference is the bracket which rotates the sensor 90 degrees to work with the aluminum uprights. The metal pickup (---) needs to be in line with the tone rings notches to give the proper pulse. My guess is they changed the housing probably to cheapen their cost for the 993 which came in at MSRP $5k less than the outgoing 964. Theoretically you could 3D print a bracket and remove the metal part and adjust the 964 units to work. Although I went with 993 units up front. They came on the set of uprights I had I purchased used years ago. Funny I paid less for the full setup both sides, sensors, tone rings bearings etc for less than the cost of the ABS sensor new today. Boy have times changed.
The 993 unit pictured below is designed to have the wire go to the backside vs the 964 which goes to the side. I believe the entire unit - the bracket is plastic cased.