Originally Posted by Markyt1984
I am rubbish at using a meter, I'm colour blind
Sir, STEP AWAY FROM THE WIRING.
Sorry couldn't help it,
Get access to the wiring at the back of the ignition switch, leave the ignition off for now.
Using your meter set to DC volts, connect the black, - negative lead to the retaining strap in the door jamb. Then using the red + probe, find the live wire by puncturing its insulation. The permanent live will show 12+volts.
Then turn on the ignition to the first position (so your radio comes on). Do the same with your meter, you will find the accessory live showing 12+volts
Then turn on the ignition to the fully on position (with ignition lights on). Do the same with your meter, you will find at least one wire that comes live with 12+volts. If you do splice into this wire, make sure you fit an extra inline fuse.