I finished installing my Blitz FATT DC2 on my '04 WRX. I'm not going to go into the details on how to install it. There are many threads here that show how to do it.
Here is the thing. The GRAY wire that's supposed to be next to the ebrake.....it's not there or anywhere. There was supposed to be a security module next to the ebrake, but I never found it. The other thing is that the PINK or PURPLE single wire that runs to the ebrake, it's not PINK or PURPLE, it's actually LIGHT GREEN. Splice into that one and your engine will shut down when the ebrake is released and the turbo timer is running.
One more thing, if you want to install a turbo timer, don't be cheap and get the harness. It makes life soo much easier.