NavList:

I typically use an artificial horizon (in my case, a cereal bowl filled with water) to take sights of sun/moon/planets/Sirius.  However, other than Sirius, I find stars too dim to make reflections in my cereal bowl.  So I used the technique Don talked about...to use an artificial horizon to measure the height of the sun as it appeared over the top of the house across the street.  Then I measured the height of the sun using the roof of the house as a horizon.  From that, I developed a diagram of the house with a unique dip correction for different portions of the roofline.

This would be pretty easy to adapt to your mountains.  If you are taking sights outside, you may need to purchase a Davis artificial horizon for $32.  It has a little tent-like arrangement of glass over the top of the water.  Here is a photo: http://sailingmagazine.net/article-608-celestial-navigation.html  This protects the water surface from stray puffs of wind that would set up ripples.

Bob