Custom front strut top mounts and camber adjustment thingies, custom solid engine mounts, custom carbon-kevlar intake manifold, custom this and that, in the rear there's custom shock mounts again (they must not fit, lol), custom subframe, custom trailing arms and control arms, nascar-style sway, etc, etc, etc.
Wow. That's the reason cars like that still work when they're slammed. They're designed for it, even though those touring cars are still using a mostly stock chassis. Imagine if it was a tube frame car with only a stock body on top. Screw Cusco, screw J's Racing, Buddy Club, or whoever, those are race car parts.
Btw, that Focus is sexy. Excellent post.