Over the past few years, I have been watching and reading about original 69 Z/28 blocks with just the pad stamped, and some with the pad stamped and partial vin. # stamped by the oil filter. I understand from this site, why they changed the location of the partial vin. # and about when, so here is my questions.
With all the factory controls in place, along with a QC system they had back then, why weren't all car/blocks confirmed to be properly stamped both on the block pad and by the oil filter after they made the change? Did it become so difficult to do during the production process to get done right, or did they just say oh what the heck, its not going to matter anyway and just let it go. Or, did they get it right and they are just that many re-stamp block out there these days.
As a hobbyist this continue to confuses me. Are there really that many re-stamps blocks out there these days and if so, about when did all the fakes start showing up.