If I were doing it I would only use an electric oven pre-heated to 350 degress. let it heat soak for about 35 - 45 min. This will allow the gear to expand to its max growth for an easy install onto the cam snout. It will not damage the gear unless you use force while it's still hot. Go to the dollar store and get some oven mittens so you can throw them away and hide the evidence and act like nothing happened!
