The V and T are much bigger than the rest of the serial code. My two 65s are not like this at all. Mine are all the same size, much deeper and very sloppy. This is from a supposed 66 tri carb vert.

 

Hard to say, warranty blocks were stamped with the original block vin by the tech doing the work. That is why you see in some instances blank pads for the tech was to lazy or forgot to stamp. The original block was destroyed.

Don't know if that be the case here but an fyi anyway.

 

Here's the stamp on my 67 the letters are much bigger. I don't believe my motor has ever been out.

67sportscoupe004.jpg

 

i had heads from 67 442 that had bigger letters also.

 

sounds like you should suspect the other heads with small letters