5 weeks apart? I could believe 5 days, or even heads a few weeks older that the block, but a 5 week pair is pushing it. What's the block date?
Guessing that this is for a San Jose 65-67 since this is a Shelby site. The ones I have on record are days apart typically - but its a small sampling
They are not on a car, they are a set that I have had in the garage for about 20 years. I have no idea as to their origin, as my father bought them years ago. I have only the heads, no block.
