HU Wiring Harness. Need Help!

[vivalaflam]

Well, I have this stereo I want to put on the Yaris (2nd gen Hatch). It came with standard integrated HU, which has no MP3 capabilities, and started skipping on CDs. I wanted to replace it since forever.
So, I started off by buying the Scosche kit and a dash kit. The dash kit came in the wrong dimensions, it was for standard 2DIN HUs (EU standard dimensions). I currently have no dash kit (to fit the stereo) but no worries, CTScott will hook me up with some of them 'murican dash kits.
Long story short, I'm familiar with all the installation and how to fit them in my yaris and all, but the wiring. You see, the stereo I want to install, I had it on my old car, a '89 Fiat Tipo, got it installed by a "professional". Anyway, as you will see in the pictures below, Im all ready to do the wiring. I have the wiring for my stereo and from the Scosche. Im asking for help to connect the wires together. The method I'm gonna use is the simple twist, and/or maybe some soldering, and then some electrical tape. Here's all the images:
^Thats the connector that plugs into the stereo.
^Thats the part Im the most curious about. Where do I need to cut the wires? I dont want to buy a new wiring harness...
^Thats the stereo Im installing. An old but awesome Sony CDX-MP80
^back of the stereo.
^The wiring harness.
^and the connections.

Below I'll post and the wiring for the stereo. I need your help so I dont make a mistake with the colours. In the FIAT, the "professional" made it that the stereo would work without a key in the ignition... I dont need that, I just need it to work. Does it make a difference?

Here's the wiring diagram of the HU:




Any suggestions, tips etc are all welcome! Thanks!


EDIT: WOW, I need to resize those photos, I uploaded them to dropbox from my phone, so how do I do that without a PC?