Hi MT,
One thing you don't want to do is hug the front shoulder too close! Try this, focus on the middle point of the bear and then go forward. If you focus on the front shoulder and try to aim a little back, chances are you will place the shot too far forward. A bears vitals are placed somewhat back more than that of a whitetail.
Broadside or slightly quarting away are perfect.
What kind of broadhead are you considering using on this hunt? Go with a fixed blade if you can get it to fly. Remember your shot will probally be under 15 yards, so don't worry about shooting the lightest arrow, or the fastest set-up. You want to shoot something that will get the job done.
If you are hunting with an outfitter, give them a call and discuss this with them. They should be more than happy to talk to you about any questions that you might have about your hunt!
Good luck.