Never begin on a valuable heirloom. The manual recommends starting with a (e.g., a $10 Soviet-era Raketa or an old Swiss Unitas 6497 clone). Follow the PDF’s chapter on disassembly – usually Chapter 3 in Fried’s manual.
: Purchase the 4th edition (which includes extra chapters on verge fusee watches and escapements) at What the Guide Covers The Watch Repairer--39-s Manual Books Pdf File