Many Civil 3D users have requested the ability to "Force North" bearings on line labels in the product for quite a awhile. As it turns out, althought there is no setting to do this exactly we can accomplish this with the use of an expression. I discussed this with a few Autodesk personel and Peter Funk, Autodesk Product Manager, put me on the right track by saying "...this should be do-able with an expression". Well, he was right the following expression, when applied in a Parcel Line Label style will accomplish just that. I created a Parcel Line Label Expression called "North Only" and defined it as...
IF(({Segment Direction} > pi/2) * ({Segment Direction} < (3*pi/2)),{Segment Direction} - pi, {Segment Direction})
IF(({Segment Direction} > pi/2) * ({Segment Direction} < (3*pi/2)),{Segment Direction} - pi, {Segment Direction})
Basically, this will subtract 180 degrees from lines in the second and third quadrants.
For some reason, my image capture will not upload at the moment, but this does work. Give it a try.