well while im rebuilding my wrecked z,im trying todo things right. so my headlight bar is a little rusty and i was wondering what all steps to use to make it shine again

 

If they are the buckets the headlights go in, just sand them down until all of the brown and black pits in the metal are gone and spray them with some rust oleum or some rust tough enamel.

 

its the whole bar that goes across and holds the headlights

 

hmm, mine was fiberglass....

You can just scuff it up with a scotchbrite pad then and then paint it.

 

The headlight bar should be fiberglass, and can be scuffed with a red scotchbrite pad, or 400 grit sand paper, then primed and painted like anything else. If you are talking about the radiator core support, then basically use the same technique as above, which is pretty much the same as for any kind of painting.
Good luck!