i dont think the bosch gt40r is for ballast resistor type or external reg set ups... im using one with electronic igniton but when used it with normal points dizzy i had hiccups as well depending on fuel type i used (was tuned for 96 octane but caltex vortex always caused backfires).
try another coil first (2nd hand one) and possibly spark plug gap (try 0.8) or leads... it sounds like an ignition problem to me.

also points can be dud sets, and if timing or ignition is bad, can burn and pitt them quite easily, do you give them a light sand with an emery board before resting and instaling the points?