Take a screwdriver and hammer and hit one side...when it spins sideways just pull it out with a pair of pliers/vice grips
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They just tap in to reinstall....use an RTV or similar sealant around it...tap in and done. Most Machine shops don't charge much to do this if you don't want to....as an example, my machine shop charges $50 to Vat, Clean, install cam bearings and freeze plugs.