I'd consider swapping the shifter for a 7-speed model if I were you. You can use any 7-speed block then.
Another alternative would be to re-space a 7-speed block using different spacers.
@rodabod started
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I'd consider swapping the shifter for a 7-speed model if I were you. You can use any 7-speed block then.
Another alternative would be to re-space a 7-speed block using different spacers.