if your plates are *say* 40mm back from stock, then its a 40mm-longer rod you need........at least to get things started.....
Don't rely on only a couple of threads to hold the shift-rod on

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Most times when you fiddle with rear-sets of any type, some other mods are needed.......I have a few *modified* shift-rods here, we can go through that and see what works........until you locate a nice shiny one of the right length.......
