If you are burning up points on a regular bases then you probably need a resistor, if not you are ok. Was your points wiped out & if so did a new set solve your problem?
A six volt coil won't need a resistor running on six volts but if you convert to 12 it has to have a resistor. Another thing that will burn up a set of points is leaving the key on for an extended period of time with the engine not running.
