Dont worry about super crazy race car. You're driving a focus.
Tune from Tom, you get the most back if you start here.
Svt header, cat back, tb and if you've got the money, cams. Not really drive train like you wanted but consider the following.
You'll see better results via suspension. I'm running vogtland springs, eibach f/r sways, +1 wheels and nice tires.
Short throw shifters feel nicer to drive.
As far as brakes go, normal rotors, nice pads and SS brake lines.
You'll have the best bang per buck focus out there
Cosmetics is all on you.