I would really look at the rear end suspension having trailing arms rather the more tradional buggy arms, the cars are very light at the rear and i don't think what you are planning will be the optimum way to go. You will need very light damping / spring and from everything i have seen trailing is the way to go.
Also with the tralining arms you will also be able to lower the c of g nicely as the shocks will no long be sticking up in the arm
and its very simple to setup camber and toe via turnbuckles which attach via the trailing arm.
Also for us to run this car in the uk, it can be no more than 250mm wide which i think could be a issue if your using a 4wd front end with rear hubs fitted, and rear tires would have to be fitted at the back of the car for it to be legal.
Btw if you get stuck for making the plastic parts give me a shout.