[Mr427]

Hi: I have a 1967 428 GT-500 block. It has absolutely no identification numbers on it, other than the C6ME-A casting number and the date code. You already have all that on your block.

Beginning in 1968 Ford stamped all blocks with the consecutive VIN number of its host vehicle. This was probably done to ease theft recovery and the like. Ford was definitely not thinking about collectors at the time.

The number you are looking for is stamped very shallow into a flat surface on the front right hand cylinder bank. To reveal it, you must sand the paint and dirt away with a fine grain sandpaper or scotchbrite - typa abrasive.

What you will find is the consecutive unit number, consisting of five numerals, possibly preceded by the relevant engine code, as for example, if you had a block out of a 1969 CJ428 it would be:
R54224 or just 54224 or whatever number the vehicle was.

From this number you ought to be able to find out what particular car the block came from through some of the companies that specilize in VIN decoding and such.