I put in a new one as the old was bent and pretty beat up. My question is that the two mounting holes are slotted, I there a reason? Something to do with setting timing/dwell. I am not running the stock Distributor (long story). I got the Mallory dual in there. I never knew how to do dwell on the thing. If you start with a lot of technical questions I am sure I won't know what you are talking about.