Theoretically; a simple change to the 3.7 final drive ratio, with the RBT taller 5th gear (0.642) would put you just over the 200 mph barrier at 6250 rpm
Realistically; It'll probably put you in a 200 mph coffin, unless you are prepared to do some serious work on the rest of the car, especially brake & suspension upgrades.
Talk to some of the guys that run the Silver State or Open Road Races for some set up tips.
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