jackknifeh wrote: ... if there were a more accurate way to adjust the angle other than just lifting the pivot. ...
With a set of feeler gauges (something like http://www.amazon.com/Lisle-68100-Deluxe-Feeler-Gauge/dp/B0009OMY9C/ref=pd_sim_sbs_auto_2
) and drill collar stop, I used the following procedure.
First lock the drill collar stop against the bottom of the pivot block. Unlock and lift the pivot block, and insert one of the feeler blades between the drill collar stop and pivot block. Lock the pivot block. Check the new angle.
Repeat as necessary with different blades of different thickness.
The typical feeler gauge set has blades between .0015 inch to .035 inch. Making .0015 inch pivot block adjustments possible.
I can easily set the angle precisely to what I want. And, as long as the drill collar stop has not been moved, go back to a previous setting.