The GM part number for the crank sensor on that engine is GM# 12598208 it is the one in the image. The part number you have (10456568) is the transmission output speed sensor. The crank position sensor is on the firewall side of the engine, just above the oil pan lip and in line with the exhaust outlet on the manifold. To get to it you go under the car, then unplug the sensor, remove it and reverse the process to install the new one. They have a habit of sticking in the block so you may want to remove it with a warm engine and gently work it out of the bore.
Once replaced you need to use a scan tool to do a CKP relearn procedure so the ECM knows the signal levels of the new sensor.
Images (Click to enlarge)
Tuesday, October 20th, 2020 AT 6:25 PM