Manual disc brakes vs power disc brakes questions

I can get a 1&1/32 " diameter bore MC . Stock from aspen/volare. Thats as close to 1" as i can find.

Still asking what car do i get a 15/16" bore one from?

...15/16 " was used on the early A body 4 piston Kelsey Hayes disc system
a cast iron master back then.