They both could be correct,, depending on application,
I would hazard a guess that 1 3/16 would prob be best on a manual brake app.. and the 15/16 for power.
The Master cyl bore would also have some bearing on which to choose..
JMO...
Isn't it recommended to use a smaller bore MC on manual brakes?
That's the only reason I was thinking the way I was.
but both rear wheel cylinder cups are sucked in and I get no movement in the shoes.