Also, depending on how much corrosion is on your AAV, the trick to disassembly seems to be to heat up the flange with a propane torch for about 3-5 minutes until you hear a popping or pinging noise - this might be the wax in the bulb boiling off or it might be the bulb-holder working free. Then cool off the brass bulb and the aluminum bulb holder that surrounds it with an ice cube. Be careful, if it's not too corroded the whole assembly might pop out on its own since it has a spring behind it!

I've taken apart three of these so far, and the less corrosion the easier it'll be. Also, if you're really digging into either part with your vise grips, you haven't used enough heat.