I didnt think the mesh looks THAT bad, but whatever you do dont get clear rear lights and DONT spray the originals black so that it barely lets light through(as some people do)
Also id leave the engine mods if you dont have much cash to spare, because you arent going to get any noticeable gains from sticking on a K&N filter or exhaust etc so just save for some more worth while mods like nice wheels and a drop as said above