^ One wheel?!? how is that even possible???
While the ST has not yet been banned for slalom, I have a very bad feeling of what is coming....
Almost the same specs as the base fiesta (rear suspension, height width..) but the ST was lowered slightly and given a marginally greater track width. the average ST track width is only 0.1" greater than the height of the car.

Couple in a 69/31 weight bias and a torsion beam rear suspension, the back end obviously does not want to stay planted, from that point you're taking chances...
I do agree that a better FSB is necessary, and would keep the car more planted, but I don't believe the base Fiesta bar is the way to go. It is a solid 22mm bar unlike the 18mm hollow bar on the ST, (presumably with a different alloy) but it is uncertain that the beefier bar is actually stronger. Why would Ford downscale the suspension bits on a "performance model"? I can't simply see it being for weight savings.
As for lowering it, coil-overs are way out of budget for the meantime, maybe not COBB springs, but I would like to finish this year of Slalom in the Street category. Although, if the car is still competing next year, there is no doubt in my mind that it will have numerous upgrades and be seated well into "STX".
Kevin, I may have been wrong when I said 1400 degrees, my memory slips sometimes. Something about 450 Celsius sounds more right. Dev was the one with the temperature gauge, so he might be able to weigh in on that. Regardless, the brakes need some serious upgrading. If it's worth doing, it's worth overdoing, I'm still leaning towards Carbotech pads and rotors, simply because so many ST owners have had similar issues to mine, and not specifically from track use, but much more googling and phone calls are required. I also managed to find a D.I.Y. thread on cooling ducts for the ST so I'll likely do something similar to that.
I guess the saying of making a race car out of a pig is still true!