The crank position sensor (CKP) on a 1999 Jeep Grand Cherokee 4.7L V8 is located on the
passenger side of the engine block, near the crankshaft pulley. It's usually mounted on the engine block itself, facing the crankshaft pulley. You'll likely need to look underneath the vehicle for easier access.
While the exact position can vary slightly depending on the specific engine configuration, it's consistently in that general area. A repair manual specific to your vehicle's year and engine would provide the most precise location.