Before you shoot it
Full dis-assembly of a Colt replica is extremely straight forward,
Click Here for a YouTube tutorial on a Dragoon. One thing he doesn't do is recommend that you check the timing after re-assembly. Mine mis-timed once when I put it back together. I pulled it apart and re-assembled and never did figure out what I did wrong.
I HIGHLY recommend a thorough cleaning and inspection BEFORE you shoot it. The packing grease can and will give you fits if it's in the nipples (don't ask how I learned this).
As far as the nipple wrench and Uberti is concerned, Dragoon/Walker nipples have slightly larger shoulders than the other Colt replicas. With the cylinder out take a tube type nipple wrench (fittings on both ends), mark one end with an awl or in some way that you use the same end all the time on the Dragoon. Then tap that end onto the nipple, the wrench is soft so the ends will spread and after a few times will fit the nipple. You could also buy a nipple wrench specifically designed for Dragoon/Walker guns.
As far as after you shoot, I personally remove nipples EVERY time I clean the gun and go after them with a tooth brush and Dawn dishwashing soap. Once installed back in the cylinder I put a dollop of oil down each to try to keep the orifice from rusting closed, so far so good. I do not use anti seize on the threads as it's a moot point if they're coming out again after I shoot. Also remember when you install the nipples that you do not have to lean on the wrench too hard to tighten them, snug works good, especially if you remove them each time you clean.
Regarding drying in the oven, I've tried it, it works but...I find that I get a considerable amount of "Flash Rust" on the inside of the chambers and barrel. I personally prefer compressed air, to each is own.
Full dis-assembly of your Dragoon as far as I'm concerned is worth the time and trouble if you want to keep it in top condition. During the winter months when we're on the road in the south, I cruise the Pawn Shops etc. looking for lost BP pistols. I've seen some horror stories inside formerly beautiful guns because they weren't properly cleaned.
Have fun, and if I might impart one other bit of hard learned wisdom regarding Dragoons and Walkers. You might want to avoid shooting a Dragoon upwind, especially if you use Crisco, 'nuf said.
Joe