Yep, I've done it. Remove all the screws from the housings BEFORE you put them in the oven and get a good set of gloves. The metal unit on the bottom (I think it's the ballast) can stay on. Iirc, I removed the low beam bulbs one time because they are so expensive, but it's not 100% necessary as they naturally get hotter than hell anyway while operating. I baked them at 220 for at least 12 minutes. I highly recommend having someone around with a screwdriver or toothpicks to help you keep the sealant from falling inside the housing while you pull the halves apart, because it gets realllllllllly stringy.
Do NOT touch the inside of the clear plastic housing....at all....period. IF you do, or you drop some shit in there and have to clean them, use a soft, lint free cotton cloth to buff them and apply some anti-fog lens cleaner, or you will hate yourself for opening them up. Make sure you also have a good quality RTV silicone or similar sealant to use. There is generally enough sealant still on the housings that you can reheat them and press them back together, but I highly recommend laying a bead of sealant over the existing sealant AFTER you push them back together and replace all the screws. Carefully smooth it down with a plastic butter knife and trim any excess with a razor blade.
I'll try to check back later on this, I am swamped at work.