Thanks for the tips Snake, much appreciated. I've had a look at GTS Pearl Blue (the Viper colour), looks a bit too dark to me. I agree that Nassau isn't an exact match and is a touch light, but to my eye it still looks like the closest thing without actually getting some LeMans blue. I think I'll test on some plastic spoons with some different colour primers and see what looks best.
Sorry to hijack the thread by the way. Both of those Corvettes looks sensational, nothing like an early C3 (68-72) on Rally wheels.