Just a thought: Have you looked into a R6 speedometer at all? I am actually considering one for a project that I am working on. they are readily available (eBay, R6-Forum, etc..) and are typically much cheaper than the 07'+ FZ speedo (As low as $145 for the R6 on eBay as compared to the typical $275+ for the 07' FZ).
Plus, if you get all of the kinks worked out then I don't have to