Wiring a new head unit

Right, i couldnt find any previous posts.
Im putting in a new head unit, and the previous owner had messed up the iso connections so need to sort it out myself. As mine has had a G60 conversion, i dont know if i have g60 wireing or MK1 GTI.
soo….

I have 5 wires sticking out from dash
(except for speaker wires)

Red and Brown
Brown and Red
Blue and White
Blue and Grey
Red and White

and i need to match them upto:
Red - electric terminal controlled by ignition
Black - Ground
Yellow - terminal always supplied with power regardless of ignition
Blue/White - not sure what that does, but i dont think its important.

Help!

see this;

http://www.installdr.com/Harnesses/VW-Wiring.pdf

I'd get an ISO harness from Maplin or Halfords and solder the wires. Then most 1990s onwards radios will simply plug in and out at will.

Note on my 87 Cabrio the speaker wires didn't match any of teh colours :dontknow:

Cheers for that. Gonna take more than i thought. Got all the right wires hooked up, but there doesn't seem to be any power the fuse is fine. Looks like im going to somehow trace the wires back!

Get a multimeter and check your getting + and earth alright,  if its been played with before, (as stereo wiring more than often has been) you may just need to run a new earth from teh earth point next teh fusebox, and live from somewhere convenient, lighter or something like that.

cheers for all your help guys, have sorted it now