Wheel cylinder bore size question

gliderider06 said
Did some more digging... 7/8 Is for 12x2.5 and 1-1/16 Is for 12 x 3"

Interesting that the more powerful one is used with the larger surface area drum...
might have been a 360 vs /6 or towing package decision.
I believe there were different GVWs as well for AW150s... but all were 1/2 tons.