Auto Parts: 1991 Geo tracker rotor button, distributor shaft, shaft sizes

Question
QUESTION: I have a 1991 Geo tracker 1.6 liter. I tried getting a rotor button at advance auto and autozone. All 3 buttons seem to fit a larger distributor shaft. The hole in the button seems to be about 0.030 larger than the old button. Any ideas on where to get the right button?
Thanks


1991-1992   ANSWER:      Did any of the rotors that you were shown look like the old one, aside from the size of the hole?  The 1991 & 1992 should use the same one, a kind of squarish dingus with rounded off corners.  The 1990 uses a more conventional rotor, solid on top with a t-shaped contact sticking out, as opposed to the spring-loaded top contact in the later models.  If you cap has a spring-loaded carbon brush inside, then it needs the 1990 rotor to go with it.  If the cap has a solid carbon contact in the center, then it needs the spring-loaded later one.  The caps look similar on the outside, and may even both fit on the distributor, but they use different rotors, and the rotors probably have different shaft sizes.  Assuming you still have the old parts, give them a close look and you'll see that there are differences in appearance on the caps as well.  I have a feeling that you will need the 1990 cap and rotor.  I'm going to attach pictures of both rotors.

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rotor   QUESTION: The old cap and the ones at the stores look exactly the same except the hole size. None of them look like the ones in the picture. The cap has a solid carbon button and the rotor is spring loaded, the shaft is triangular with rounded corners. Here is a picture of the one I got at advance auto.
Thanks

Answer
   Well it sure looks like the right one (I sent you the wrong picture).  Is it possible that the new rotor was missing that metal clip on the inside of the hole?  I've seen that before, and it would make the difference you're talking about.  If it's not that, I don't know what to say.