I owned a 96 C9 and a 95 F1, two completely different bikes. The C9 said Ninja 600R on the side, and was the same boxy styled fairings and steel tube frame that they dreamed up all the way back in 88; and it was a slug compared to my F1. The F models looked very similar to the G models as far as fairing shape goes, as well as the E models. As for the D & E models, thats when they were kinda transitioning the 600 into the super sport bike; I could be wrong but I'm fairly certain that the engine got totally redesigned in 95 as well as some chassis modifications, and thats why they tacked the "R" on the end. Maybe it had something to do with the racing classes too, anyone know what the first year of the 600 super sport class was?
I don't know a whole lot about the GPZ line, weren't they kinda the predecessor to the ZX line and they stopped making them in like 85 or so?
If you want the breakdown on fuel management systems, take some time to read this thread. For a walk through on pulling FI Codes, check out this thread. Questions about Flashed ECUs vs. Fuel Controllers? Try this one. Got a Z-Fi TC System? Read This to get an idea of how it works. Here's a link to some Kawasaki Service Manuals that I've got hosted for everyone's use. And please check out my blog for more sage advice and technical ramblings. Some basics about braking here.