Well I got bored so I did a search myself, didn't come up with much but I did find some Reverse Style Illumiglo gauges for the 636. They are Here. That tach that is at that link is pretty much the same deal though. I think you might have to get a whole new gauge pod to replace the old digital tach
Try contacting www.attackperformance.com . They would be able to point you to any aftermarket solutions. They have a fully programmable instrument cluster on their race bikes but I cringe to think how much that unit will cost. I've called them before and they are a really nice bunch of people. Will be willing to help you out even if they're not selling you anything. Incidentally, they're the aftermarket cooperative for Kawasaki's racing program.
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