Always going to struggle with the 9 speed vs 8 speed as the spacing is different between cogs (something like 0.5mm if I remember right) and the cable pull in index mode for that shifter is 9 speed compatable - I'm sure you know that! I could be wrong, but I thought that shifter could be used in friction mode too .. then you can "feel the change" old school like!
Always going to struggle with the 9 speed vs 8 speed as the spacing is different between cogs (something like 0.5mm if I remember right) and the cable pull in index mode for that shifter is 9 speed compatable - I'm sure you know that! I could be wrong, but I thought that shifter could be used in friction mode too .. then you can "feel the change" old school like!