wthx100

I installed a set of stoptechs and the driver side is fine but the passenger side rubs on the wheel. The top of the caliper has 2mm clearance but the bottom of the caliper hits the wheel. I tried wiggling the tire top to bottom to check for play in the wheel bearing but it's tight. Do fd's have servicable wheel bearings or do i have to get a new hub/bearing combo?
Also what is the difference between hubcentric spacers and normal spacers. Can all wheels use hubcentric spacers? I'm thinking to get some 3mm spacers just for added safety would this require longer bolts?