For rough pointing, a decent GPS is one of the best tools to have in your kit.
Mark a waypoint at location 1, go to location 2, and tell the GPS you want to aim at location 1. It will give you the absolute bearing ... and in some cases, give you a pointer.
If the distances are out of visual range, the spread of the beam will give you up to a couple degrees of error for the azimuth to catch the signal.
If the distances are not too far, you may be able to use a strobe for a visual rough-point.
You can use the bridges themselves (the signal strength) to peak the systems out.
If there is an elevation difference, you will also have to compensate vertically (again, the GPS can give you fairly close altitude readings .. you may need to do a little math for slope-over-distance).
Good Luck
Scott
