I have an '81 with standard ignition with points, but may later go pointless. I want to be able to verify and adjust my timing, not only at idle, but also as I'm driving at different RPM and load, to verify the mechanical and vacuum advance are getting the engine into the best timing for all circumstances. I am familiar with a timing light from my teenage years. Can someone tell me how a dwell meter is different and pro and cons between the two? Also, suggestions for doing what I want to do?
Thanks!

A dwell meter tells you how long (or how many degrees) your points are staying closed. In a GM 8 cylinder prior to '75 the dwell should be from 28-32 degrees, with 30 degrees being optimum. That's 30 degrees of rotation of the distributor shaft the points are closed. In a good car, the dwell should stay unchanged throughout the usable rpm band. At some point you would get "point bounce" when the rpm's get too high or if the points have a weak spring.

Dwell stays unchanged regardless of timing, but timing changes with dwell variations. That's why dwell is set first before setting basic timing. As points wear, timing will change. That's why electronic ignition is so superior...timing should theoretically never change since dwell should never change in an electronic unit. Of course, that doesn't take into account distributor wear or timing chain wear over time. With no points to wear or get burned, the spark energy stays much more constant and at a much higher voltage than with a point ignition.

After your dwell is set, then set timing according to your car's specs and instructions.

I don't know why you're running point ignition in a car that originally came with electronic ignition, but you'll be miles ahead going back to HEI.

I agree, go back to HEI. Unless you are reving over 6500 or so it is virtually bulletproof.

If you have a point ignition in a 81 something is terribly wrong! GM went to HEI in 73!
Steve