More to follow when I get time to scan & post some diagrams but for now: The UK generic term for this fuze is Fuze Nose Mechanical Time L81. It was still in use with UK forces in 1979, in 105 mm Howitzer illuminating shell (L55A1) and 105 mm Field illuminating shell (L43A1).
The body is made of nickel plated brass and is screw threaded for attachment of the magazine. A Vernier scale is engraved on the conical surface of the body, with graduations from 0 - 10 to permit greater accuracy of time setting. The fuze has an aluminium nose, around the base are graduations from 0 - 60, representing seconds. The main part of the fuze is the mechanical time element. This consists of the escapement housing, driving device, timing gear, escapement mechanism and detonator with striker. A magazine containing gunpowder is attached at the base of the fuze body. One of the fuze safety arrangements is that the fuze is set on the maximum time setting (60) before issue and without sustained centrifugal force, the time element is immobile.
From what I can see from the diagrams I wouldn't recommend disassembling yours, unless you are skilled at repairing watches. More a work of art than a fuze. Will post more when I get time. XT