There are primary and the secondary locations of the VIN derivative on the rear of the engine block on all C5's including Z06s. Also, there are primary, secondary, and optional serial numbers on locations on the transmission. You should find "stick-on" labels attached to the engine, laser etching, or stampings in the engine block indicate the engine unit number/build date code. Also the engine ID number will be located on the rear of LH cylinder head or the front part of LH oil pan rail. There are more legible when viewed from underneath the car.