Basically you want as much dwell as you can get and still have sufficient
discharge time when the points break. So the numbers you quote for dwell
are good.

My practice for about the past 20 years has been to leave whatever is there
connected (vacuum advance etc) and set them to about 20° advanced. It has
worked very well for me. You will know pretty quick if it is too much by
pinging/pinking under heavy loads at medium speeds, especially when the
engine is hot. In that case retard it a couple degrees.

Normally the vacuum advance gives you about 10° so if you disconnect it it
slows the idle way down and you have to readjust the idle speed to keep it
running. Then you set it to 10°, hook the vac back up and it idles way too
fast so you have to adjust the idle back down. Setting it with the vac
still connected avoids all the adjustment and readjustment and still gives
good timing - what you see is what you get.
--
George Downs Bartlesville, Heart of the USA!