Milling the rear brake caliper and adding a spacer to the left side is a solution when mounting a new wider rim and tire using the existing rear HD caliper. I have a 2004 FatBoy with the same offset problem and I want to put on a new PM pully and 18x4.25 rim with 160/60-18 Metzeler on the back. I am also wanting to replace the rear brake with a one piece PM brake caliper. My question is, will I need to mill the PM caliper and space the left side like the OEM solution or will the PM pully, rim and caliper bolt together and center the tire in the fender with only a .125 spacer on the left side?

Thanks
Zaner