Hi James, I found the markings on the jacket on the opposite side to the oil gravity tank, and as far as I know they are for the Herts & Beds Yeomanry, 201 Field Battery. I have seen some old pictures with markings/numbers on the trail, but I think from memory they were on the other side of the carriage from yours, though this is not to say they wouldn't have been on both sides. I will try and find them again!! I got them in 2007. Cheers, Mel