I'm about to switch from a late 2-bolt aluminum 1 1/8" bore to a similar 1 1/32" bore. I like a hard pedal (manual brakes) but the big bore was too much. I ran it for about a year anyway! It stops but it needs lots of pressure. I am 6' 2" 300lbs...

I think 7/8"-1 1/32" is a good range with this setup.

By the way I still have 10" drum brakes on the back. I swapped in an a-body disc prop valve with an aftermarket adjustable knob style behind it to control premature lockup. It turns out with 275/60/15's on the back (28" tire) the extra knob wasn't needed. I just run it wide open to the rear. Maybe 26" tall tires would need a little line pressure taken away?

Hope I helped.