Nice lookin bike! Love the orange, it's about the same as my moto hardtail.

As for disc brakes, I also had some trouble. I found that the recommended method of loosen bolts, squeeze brake, tighten bolts, was not sufficient. I had to enlist a third hand and also nudge the caliper in the desired direction, and tighten very slowly & carefully, trying not to let the force of the bolts disturb anything.