Braking Help

I have an issue with a braking problem. The car pulls mildly left. I have replaced flexible hoses, calipers, and pads (on both sides, even though I know the issue is supposed to be on the passenger side). While changing the calipers, I noticed the drivers side rotor was very difficult to spin. If I tighten the caliper bolts tight, the rotor wont spin, until I back off the caliper bolts a few turns. The only thing I haven't tried is new rotors and checking brake pressure at each caliper. Any thoughts would be helpful.

Jonas