The way that i have done it is so that if i do have a hard enough impact to bend any ally parts there are plastic where the most pressure will be so they will snap before the ally bends. It used to be on the heavy side but now that im running the lightweight diffs it has done down to about 2g over the legal limit rather than having to keep it weighted to keep it above so it doesnt effect the handling of the car. Im gettin a BMI chassis conversion soon so that might get rid of more weight