I've installed countless 5712 moonphases, both rep and gen at this point.
- Genuine has a very high chance (I say 40% likely) of cracking the glass when removing from the brass gear (if that's the one you get). A competent watchmaker can save each piece of glass and reconstruct it if necessary. It cannot be heated off, someone tried that and sent me their moonphase to try and get off, which I did without breaking it, but the paint melted onto the lower brass gear. I had to paint what I could to fix it on the underside.
- Rep moonphase discs are installed as an overlay on the existing gear. This adds thickness. You must give a tiny bit of extra clearance room for the moonphase to move, but this can prevent the already small collar of the date hand to properly engage without scratching the dial. It's a careful balancing act.
- The top post that the dial installs into (that is on the movement) must be filed down if you want to install a rep dial from SWF. The post is actually on the movement. I also received a movement from someone else where the 'watchmaker' filed down the post while it was (1) still in the case and (2) didn't remove any plates while filing it down. The filing shavings got everywhere in the movement.
I've had a few send me their local watchmaker attempts at either servicing or modding this watch. Seems like some understand it and others rarely see this type of complication (?).
My recommendation is to always send to someone you trust to do the mods who is experienced. The only replacement parts are either buying a new rep movement, which is both expensive and can take a loooong time, or buying already rare and expensive gen parts that sometimes cost more than the rep movement itself.
