The job number tells you the sequential number of your car as to when it was built during that model year, therefore if your job number is 21,633, your C5 was the 21,633rd built in that particular model year. Z19 is the hardtop option for '99 and '00 which represented the Z51 handling package, 6-spd transmission, big wheels and tires, the same as the coupe and convertible. Originally the hardtop was designed to have 17 inch tires all the way around but it was never produced like that. The original idea for the hardtop was to produce a low cost Corvette which came one way with an automatic, 17 inch wheels, and cloth seats. That idea was abandoned before production started in favor of a hot rod Corvette which was built for performance rather than a low price.
My job number is 33255, which means it was built on June 28th on a Monday. If anyone wants to know, I'll post the informaton. Please let me know how interested you are. You can find the job number when you open the trunk and lift the compartment cover. It's underneath the cover. It will have the letters SEQ NUM before it
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