if you get a 1 wire remember that it will not charge at low rpm's the power master trigers at @ 2000 rpm's <alt shaft speed>
not true...Quote from Power Master
A one wire alternator has a turn on point (sometimes called cut in, which is typically 1200 engine RPMs). This is the speed where the internal sense circuitry connects the battery to the voltage regulator, thereby turning the alternator on. Once the voltage regulator turns on, the alternator will remain on and charging until the engine comes to a complete stop. If the engine idle speed and pulley ratio combination do not allow the alternator to come up to this point during starting, the engine will have to be revved up to turn the one wire alternator on. The sense circuitry in the one-wire regulator can be bypassed to excite the alternator as soon as the ignition switch is turned on. This is called three-wire operation. This means the alternator will not be dependent on reaching a certain turn on RPM.