The wiring harness was very straight forward to make, you are only really adding 5 wires to the ECU side and 4 to the actual plug that goes to the motor. The biggest pain is repinning the ECU, but with the right tools, or in my case improvised tools, you can build one yourself. I suppose I could do a write up on it, but it might take a few days.
Unless you are going to be doing serious racing, stick with the STI pan, baffle and pick up. Not knocking Killer B's stuff, but out of all the cars I have worked on and built over the past years, I have never seen one with a bad pick up. Clogged because they didn't care for the motor, yes, but never broke.
The banjo bolt on the cylinder head to the AVCS and turbo, pull the screen out of it.
If you do the ECU swap, for the love off all that is holy, DO NOT PLUG THE ECU IN WITH THE BATTERY HOOKED UP!!! Make sure your connections are correct or you can fry the ecu.
Resident Grumpy Old Man(Keith)
03 WRX 2.0L
08' LGT Gears
Spec C goodies