Attached is what I think the markings and colours would be. Please note that I only used a generic font to make this quick graphic, so it't not a perfect match with the picture!
Also attached is a picture of a Sexton from B troop, 23rd Field Regiment, which would be 31st Battery. Picture taken in Diepenheim 1945, source:
https://mijnstadmijndorp.nl/app/old-...7&id=324200179
Also attached is a picture of a Sexton from F troop, 23rd Field Regiment, 83rd Battery. Picture posted here on the forum by Bryan Naylor in this thread:
http://www.mapleleafup.net/forums/sh...d.php?p=100364
Both pictures give an idea of the location of the markings, but Bryans picture also shows the Tactical sign of F troop, with the red square in the lower left corner of the blue background, this matches the info on the Wiki page (3rd battery in 23rd Field regiment with Easy and Fox troops) :
https://en.wikipedia.org/wiki/23rd_Field_Regiment,_RCA
This would mean that indeed the red square for "Darling" would be in the lower right corner of the tactical sign, as 36th battery is the 2nd battery in 23rd Field regiment.
last picture attached is a screenshot from the "The Royal Artillery 1939-1945" website. source:
https://ra39-45.co.uk/formations-and...hicle-markings