jegs:
130-46112 get you a shift knob with the switch already installed
741-15879 will get you a throttle switch
741-15606 is a covered switch similar to arcraft switches, a good master switch for the whole system.
as far a wiring it all up........
in order, the master switch will come first, followed by the throttle switch, so you are at full throttle, and not wasing that shot of n02. Then the knob switch, so it is activated only when you really want to use it. Apply the output of the final switch to a 20 or 30 amp realy, use the output of the relay to fire both the fuel and n02 selonids, and make sure you have plenty of fuel pressure. as an added safety, 741-15750 is a fuel pressure switch that will shut off your system is the fuel presure drops below a safe range, not sure if it is calibrated to a carb system or a high pressure fuel injection system