One other difference is some starters have an extra terminal, on early K-Jet cars it connects to a brown wire. The brown wire powers the coil while the starter is cranking and bypasses the ballast resistor that the blue (switched +12V) wire runs through. I assume this is to give a stronger spark while cranking or something but I don't really know. If your car has that brown wire, you can disconnect it, just wrap the unused terminal in some electrical tape as it will have +volts on it when the car is running.
