weight of parts

I try and look at a part on the car and ask. Can I get ride of it? If not can I replace it with some thing lighter? If not can I some how take that part and lighten it in some way? IE cut some unneeded stuff off it or the good old drill it full of holes.

I don't want to drill it full of holes because its gonna be driven on the street.But i'd like to make it light as possible..