[Mk2] [Generic] Sony WX-C570R radio/cassette/CD head unit wiring connections

[NATKIN]

I am wanting to fit a Sony WX-C570R double din radio/cassette/CD head unit to my Toyota MR2 MK2 1993 model (G Limited)
The Head Unit has a 16 pin plug on its rear from which there are:-
(a) 10 different coloured wires connected to a 10 pin plug
(b) 4 different coloured wires connected to a 6 pin plug (2 pins not used) and
(c) 1 coloured wire which is not connected to either of the two plugs but is labelled 'ATT'
Can anybody help me as to which of the coloured wires connect to what and what does ATT stand for.
I presume that at least 8 of the wires will connect to the front/rear speakers and that there will be a wire connected to a Permanent 12v supply from the Battery, a wire connected to a 12v switched supply from the IGN switch and also a wire to Ground (Earth)
Probably the other remaining wires are for an electric aerial but any help or suggestions would be appreciated.

[DeusMR2]

10 pin plug is probably for speakers and accesories
6 pin plug is for constant +12V, switched +12V & ground

I think ATT is short for Attenuation, it has the same effect as pressing the ATT button on the front of most headunits. It instantly lowers the volume for when you get a call etc. Pressing the button again restores the volume. The wire is normally conencted to a 3rd party in-car phone accessory but it's rare.

Full wiring colours are here:
http://www.the12volt.com/installbay/veh ... oyota.html

Note that depending if you have the "active" or "passive" sound system the colours will be different.

The easy option is just to buy an adaptor and plug it straight in. Autoleads PC9-411 or PC9-409 depending on your car.