Neutral safety switch and fuse rating

[bestdog]

Hellow all.
I have started my rover fuel injection conversion, 2 issues have pop-up. 1st-, how to deal with the neutral safety switch, the ECU only wants 5 volt input , if i just ground the wire i will be sending 12 volts to the ECU i worry i would fry the ECU. 2nd .- fuel pump requires a fuse, i do not have the wiring diagram for the whole R.R. so i do not know the rating. My set up is MGB with 3.9 Lt Rover engine and stock Rover fuel injection, Rover 5 speed trans.
I know many of you have gone down this road before me, and aquired the knowlege. Would you guys mind sharing this info with a novice?.
  Thank you all.
 Romney.

[lars49]

Romney,

The fuse is there to protect the wire not the pump.  Typically fuses are rated at 80% of the current capacity of the wire. For the safety switch you need a voltage divider.  Is the switch connecting to ground and 12 volts?  I don't understand your circuit if you are grounding the switch how are you getting 12 volts to the ECU?