Inside micrometer

   I scored an older unit complete with all the rods ...but they are not set correctly . The 1.5-2.5" is off by about .009" short of 1.5 when the thimble is zeroed . Looking into the end that goes into the head I see a setscrew . I think this is used to set the rod length but I want to be sure of procedure before I go reefing on it . The other question I have is about the "extended" setting . The head only has .500 of travel and there are 2 setscrew dimples in the mounting sleeves . When in the "long" dimple it's about .050" short .  I suspect there must have been a .500 sleeve that set the proper length in the long position . Any help will be appreciated !
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Snag
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