No pad overhang on mine dba say 1 or 2mm is acceptable. I originally tried the s12w caliper and it doesn't allow enough room for mods to fit rotor hat in. Also pads are to big and have about 5mm overhang .even if you grind pad bottom down top clearance happens due to pins to hold pads in.
I've taken heaps of pics so I can share the info next week if it's wanted.

Pretty sure won't have to grind bottom pad.

Oh and a need a right side s12+8 :)