OK, i will try again, what is the problem you are facing?
It's been 3 moths and you have not found the diagram, but have you been trying?
Get the right wiring adapter for your head unit to ISO standard.
Then only real issues i can see you having are:
- the new stereo will not turn on -because you need to use a multimeter to find and move 1-2 wires, for the power(should be switched power..take it from the +12v cigarette lighter), and then a constant +12v for memory. You will need your new head unit's diagram to move those wires accordingly.
- the steering wheel controls will not work - because the controls work through the CAN network. And most head units do not support that, you need to find that out yourself. There are some CAN -to -whatever adapters that can make the controls work.. but i have no idea what/if any are going to work with your setup.
At this time i'm sure i did more research on the damn thing than you.