NMT1957

Well I had to bring this up again since I'm looking to install my dipstick tube tonight. I have a 69 427/400, no air conditioning, July 7 build date, which I understand takes a shorter dipstck and tube than a car with air conditioning. I have a green dipstick that is 18" from under the cap to the tip, however I highly doubt mine is original at all. From what I see above I would need a red or even white tip dipstick, but I think it would be much longer than the one I have.

Also, what head marking is on the bolt that holds the dipstick tube to the block??