I recently purchased a CAC1110-0 Formula 1 Chronograph knowing it was missing the crown. The stem is still there and the watch runs flawlessly. My question is how do I replace the crown? I purchased one (7.8 MM) online and the dealer said it would work, but the crown does not fit into the stem on the watch. I measured my other Tag's with a digital caliper and they seem to be 7.8 MM. The replacement did come with a stem of its own and it looks a little different than the one on the watch. I am thinking I purchased the wrong replacement part, or it's just not as easy as screwing the crown into the existing stem. Any advice or guidance greatly appreciated.