Dean, when I first traded for my 69 Z28 in '76, and knowing it was all original (based on it's condition and history at the time), when I inspected the pad, and found NO VIN stamp, but correct engine assembly stamp, I was *very confused*, becuase all the other Z28s I'd had and knew about up til that time had the VIN on the pad. I went close to 10 yrs before I learned thru a car magazine ad, that 'late Norwood' cars had the VIN stamped into the cast surface above the oil filter boss. Knowing the car was original, I NEVER considered 'stamping' the VIN in myself! Instead, once I learned about the different stamping location, it only remained for me to pull the engine so I could *verify*, which I finally did in the late 80's and went to great extremes before I could even *detect* the stamping... special light, sunlight, enhanced high res photos, etc. My point is, I think someone would ONLY stamp something into an original part IF they had strong suspicions already, that it was a 'fake'.. and the only wanted to make it a 'better fake'... at least, that's MY opinion.