I processed 10 Muscovies this weekend. They were 8.5-9.5 weeks old. The drakes had a processed weight of about 6.5 lbs and and hens were closer to 4.0. We have a Featherman plucker and scalding tank. We also waxed the bids to get pin feathers off. We did the ducks at the end of a day where we also did 20 Freedom Rangers. The scalding time on the ducks was about 4x as long to get feathers off as compared to the chickens. The wax was a complete mess. I'll be scraping wax for weeks. In the end the bids came out mostly clean and only needed a couple pin feathers pulled by hand at the end. This was my first attempt processing Muscovies. I hope they are tasty--We'll try the first one this weekend. At this point, I'm not sure I ever want to do it again--chickens were so much easier. I was reminded of the phrase "Duck is a 4 letter word". Happy to answer any questions.
You will love the meat. We hatch out 150 - 200 muscovys at one time. We have processed as many as 40 drakes in a day. It's a lot of hard work but it pays off in the end when you have that much meat in your freezer. We waxed and skinned.