What is your goal with your "fast car"? You will never be the fastest guy in town if you are on a budget, So what is your goal? You said over on bs I think that with your currant setup that pretty close to 400whp is doable. Well 400whp is a tic less that Derick's blown mach1 made that went low 12's high 11's I think (someone chime in with his best I forget) Why not do this take the sixer to its max minus a tic to keep it together (gonna be way cheaper than a swap and WAY cooler) then take some of the money and pay some rent to your parents (things are tight in this econ. I am sure they whould not mind) take a little more and start a savings account for a appartment/house (one day soon the switch will flip and you will give anything to be out ) and then go apply to school and pay cash and not have loans that will haunt you after you leave school.
Ps. Fast cars are cooler if you build it than buy it, Cooler yet if you kick ass with less cubes