I just rebuilt a Omega caliber 1342. I finally succeeded but it was a very learning lesson. I found that there is a sleeve to install a more available battery. I also found trouble with the date changing mechanism that involves plastic parts. Cleanliness is very important for these to work properly. Also, I found that the magnetized gears that change the date are very touchy so anyone fiddling with that part beware to not try to de-magnetize this watch. It was a fun and challenging project that I won. Cool.