question.. do you need the shift light. perhaps it is Gods way of saying "rev the crap out of that motor"...
NO..
first, the shift light is not the rev limiter, just the point to shift for optimal fuel/milage
I am not too sure where the the shift light gets it's rpm signal from, I would guess there would be two locations one needs to be near the transmission, and the other somewhere in either the guage cluster or at the engine somewhere In my YJ, the shift light will only come on when in gear, and above 2500 rpms. so this is what I am basing it on.