Manual disc brake master cylinder?

pishta said

CARDONE 101326 manual disk/drum. 1.00 bore, kinda hard.....$30.
https://www.rockauto.com/en/moreinfo.php?pk=259242&cc=1328745&jsn=2262&_nck=ZExt1ysfqhqWnq+EvUNdS3Txyey60IDtnjPWF5UU9J0BWQv7pvqZbkEUk86+AYIh3BPX4eQfsOg1EffawgWWRoFzpqiw0Jm/GyISOp4ogUXswHF0aDvEhOjX1qAalB5b/rzwF/O62GNWGVNArndCnZXi8mClgDdnWQ94odXleBIjfx820k649nG9U33ihLv1pZtiWF1dveOv2K0e8OSAdVKkgKR7o5KAaLT6wbDgLRteYOOFutOUF8o5R61PiPvhM4edVcl7GEh8J/MbkfebKzygIL2QjHwrLyifKKjuJOoA53dyIQBh5339+Nhl1keekPpFe/V9IPQSkq1QydJbn6Xbvb695vWI&jsn=2262&_nck=ZExt1ysfqhqWnq+EvUNdS3Txyey60IDtnjPWF5UU9J0BWQv7pvqZbkEUk86+AYIh3BPX4eQfsOg1EffawgWWRoFzpqiw0Jm/GyISOp4ogUXswHF0aDvEhOjX1qAalB5b/rzwF/O62GNWGVNArndCnZXi8mClgDdnWQ94odXleBIjfx820k649nG9U33ihLv1pZtiWF1dveOv2K0e8OSAdVKkgKR7o5KAaLT6wbDgLRteYOOFutOUF8o5R61PiPvhM4edVcl7GEh8J/MbkfebKzygIL2QjHwrLyifKKjuJOoA53dyIQBh5339+Nhl1keekPpFe/V9IPQSkq1QydJbn6Xbvb695vWI

Click to expand...

Im looking for a 15/16 bore but this one may have to work. Shouldn’t the resivours be different sizes though if I have drums in the back and disc in the front?