Shift light, tach, by ear, rev limiter; what's your choice

I shift by feel. If you know your engine you will feel it get to peak by the way the car is moving out. Can't hear anything with another car next door at full song.

If I rev it too far the window switch turns off the nitrous. 1st sign to shift. If I am still on vacation it hits the limiter. 2nd sign to shift. By now we are losing and the rest is arbitrary.