Possible to replace housing?

I see on online markets a lot of third party gold or alternative color housing frames for the Apple Watch available, and I am also seeing photos of watches that have been able to be successfully repaired in the reviews for the housings. There aren't any videos or guides that explain how to go about this and by watching the teardown video, it seems near impossible because they had to rip out a soldered connection at the end. So how are these people doing it? I mean these things are being sold because it is possible to install somehow, right?