Struggling to know where to fit this resistor!
 

To stop run on when my isolator switch is turned off i need to fit this resistor but where does it go ?

http://i2.photobucket.com/albums/y17...s/resistor.jpg

Between the switch and ground.
It's not made to prevent run on (that is what the second pair of smaller connections labeled "2" at the bottom of the switch is for, the "2" circuit opens up when the switch is used, and cuts power to the ignitor)
It is made to suppress a potentially (to the car) harmfull voltage spike (from the running alternator) when the switch is flicked.
This way the electrical system can bleed the remaining current to ground.

Make sure to fit the wiring correctly, as the "1" circuit works exactly the other way round (circuit is open when the switch is in the ON position, and closes when the switch is flicked)
Also, fit the resistor on the wiring run from the switch to the engine bay fuse box (as that is going to get the alternators current spike), not the wiring from the battery to the switch.

http://www.holden.co.uk/productimagesWD/020_011.jpg

Thanks perfect had the same drawing just wanted the explanation as to why and where perfect cheers mate

My idol switch dosnt have the other 4 terminals on the base do can I just connect 1 end of res to earth and other to same big terminal for car electric feed

Sounds like you dont have the correct type FIA switch then.

It needs to be as per the drawing, the last thing you want is to be killing an ECU etc.

The 2 pole ones (without the 4 little electrical connectors on the bottom) can not be made to work with the resistor.
The trick of terminal pair 1 from the above drawing is that they aren't connected when the switch is on, they connect when the switch is turned off.

When you flick a 2 pole switch the power is cut.
When you would connect the resistor to the wiring when using a 2 pole switch the resistor is instantly fried when the switch is on (as full power goes through it)