Clamps on the pinion yoke in front of the seal. Includes angle mounting bracket for the proximity switch to mount onto a 9" Ford third member, and ring with 2.187" I.D. for large pinion 35 spline pinion yoke. Includes 8 magnets (p/n 57643). Proximity sensor switch sold separately as part number 57644.

Installation - Service instructions can be found on Service Bulletin #0043.