jury rig barrel adjuster?
Anyone have an idea to help convert a vintage shimano 600 rear derailleur into index? I was recently given a pair of 7 speed shift levers to replace the old friction set. The difficulty I have is that the derailleur was not built with a barrel adjuster in the rear where the cable passes through to the cable lock nut. There is a space that , on later models, was threaded to accept an adjuster. Any thoughts on rigging something up to provide a tension adjuster of some sort to allow fine tuning for the index?