Let me suggest an alternate method. Instead of powering the test light with battery voltage, ground the lead from the test light and turn the ignition switch to the "run" position. Touch the point of the tester to the insulated point, or the wire going to it. As long as the points are closed, the light will not burn because the points are providing a low-resistance ground. Turn the distributor housing opposite the direction of rotation until the points just break- - - - -the light will come on as soon as the circuit across the points is broken.
If you have two sets of points in parallel, one will probably break slightly before the other to increase the coil saturation without setting an excessively narrow gap. The "leading" point will initiate the current flow through the coil primary, and the "lagging" point will be the last one to open, creating the spark. For instance, the old Corvette 283 dual-point distributor had to be set with a dwell of about 24-25 degrees for each point, but the combined dwell of the two together was around 35 degrees. A single-point dizzy couldn't be set above 32 degrees effectively.
Jerry
