yeah i run a slotted one on my P.s pump and i only run one. be careful with a single one though. oregon is wet and i hit big puddles with it and have gotten my belt wet enough (because its slotted) that ive lost power steering for a second. 10" wheel+no power steering almost hit a car.

 

Yes the bracket will work, and either belt can be left on. I'd go with the inside closest to the pump since it's easiest to leave and wont put as much leverage pressure on your pump shaft.