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Couple of comments:
1. The plumb-bob method works well enough to get you within half a degree, provided you know your longitude and can calculate the time the sun passes over the meridian (this is usually not noon).
2. Regarding the laser pointer idea to repeatably align the mount in azimuth - it's sound - but you can get by with only one laser. You can even compensate for misalignment between the laser and scope.
Assuming
a) you have got the mount accurately aligned by one means or another, and
b) the laser and the scope are optically aligned (eg by checking optically on a star)
the procedure is:
a) Turn the scope so the dec axis is horizontal and the scope is pointing at the south celestial pole.
b) Turn on the laser.
c) With the RA locked, swing the scope downwards (using dec axis only) until the laser hits something (on a wall or fence etc) due south of the mount, where you can place a permanent marker. Even a peg in the ground will do.
d) Flip the scope over in declination so the laser is pointing north, and place another marker on the north side (on a wall or fence etc).
Now you have two marks - one north and one south.
Next time you set up the scope, assuming the laser will stay repeatably aligned with the scope all you have to do is clamp the RA axis such that the dec axis is horizontal, and turn the mount in azimuth so the laser hits the south mark.
Then check to see if the laser also strikes the north mark when the scope is flipped 180 degrees in dec. If it doesn't, it means the laser is not in the same alignment with the scope as it was when you made the initial marks. To correct for this, adjust the azimuth of the mount so that the laser mises the marks by an equal and opposite amount.
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