Those numbers refer to a part number, not a size, ck them with a number drill set, I'm bettin they've been drilled out, you need to get a handle on it, ck them, so you'll know for sure, and, if you have a Dyna, you could have a module going, or gone bad. Go to cb750supply.com, and you'll see what I mean, they are just a reference number. They also have a very nice ignition system available there, and a lot cheaper than a Dyna! Bob