For a USA model A12 engine without a dipstick tube and just a hole in the block The length of the dipstick is 9 1/16 inches
This particular example is from a 1972 coupe and or sedan motor and is measured from the bottom of the rubber stopper, it is an even 10 inches from the top of the hole drilled in the block.
Kelmo
Edit: Just read your reply to Dodgeman, and it would appear the info I supplied will not do you much good

, sorry