Checking measurement - comptip joint lip to bottom of tang

Quick favor to ask - I'm waiting on my boat to arrive and am working on making a 3 pc backer plate to epoxy inside my spare comptip I'm modding.... (one to reinforce the two front tang holes and two side plates for the other rivets)

What is the correct measurement for the tang mounting on the comptip. Measured from the LIP where the sections meet (not the end of the part that goes inside the other mast section) to the tang (at the hole where d ring goes)

(Trying to ensure I have the backer I'm making from the scrap mast covering the right spot)

Would greatly appreciate a measurement for anyone with their wave handy.

(It looks from the online pics like the tang sits about 6-12" up from the line where it joins)

I measure 12.5" from the lip to the centerline of the hole the shackle will go through.

Thank you!