Can you put up a pix of yours for comparison purposes? I'd love to see others.
Mine looks clear in that pix because I *removed the engine just to check*, cleaned carefully, was examining with magnifiers, etc... all over it *outside* in bright daylight and still couldn't find it for awhile...... When I found it I was elated, because I'd wondered for years why my front pad didn't have the VIN on it like my friends's '69 Z28... Anyway, I took pains to get that photo to capture the numbers as clearly as possible, because they are impossible to see with the engine in the car.
ps. I worked as an imaging engineer for 30 yrs developing imaging equipment for missile sensors, and aerial and satellite photo imaging; I learned a few tricks..