Dave,
Rather than setting the beam on a ladder to try to
tune it, stand it up so that it's pointed straight up.
The step-ladder thing won't get it even close.
As for using a tripode on your roof, it just depends
on how your house is built. Is it in good structural
shape? Built strong enugh to take the weight and other
stresses that will be present? Beats me! You'll have
to answer that.
'Doc

PS - If you decide to sell, I'll give you $20, you pay
shipping. After all, it's at least 7 years old. All
the electrons have leaked out of it by now...