I searched for a while but couldn't find a diagram or list for the connector of the OEM head unit.

Most are pretty obvious: power, earth, back up, speakers etc.

But for those wiring up and aftermarket headunit a diagram would be good. Is there on already or should I do one up?

 

here's a page with all kinds of useful information, including the
diagram you're looking for:
http://users.rcn.com/dhintz/Michelle/Audio/audio.html

 

Thanks oth, exactly what I need.

It's also the head unit I first installed in my car back in 2001 with the PAC control unit.

 

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