I just installed a set of silver stars and went to put the dust covers back on. its like they're damaged or to lose or something. they wont stay on. i've tired over and over again they are just too loose now. will this hurt my new headlights? 
Are they actually broken?? If you didn't break anything there's no reason they shoudln't just go right back on. I had a similar issue when replacing the headlight bulbs in the Escort, it felt like I was putting it on, but yet it was loose.
Turns out, I wasn't pushing hard enough to force the thing back in place; sometimes it's kind of a tight fit, that's how it keeps a tight seal against anything getting inside the housing. If it helps, take out the headlights (or one of them) and examine the fitting (with the red rubber) to see how it attaches to the headlight housing. Should be some kind of twist and lock type blades molded into the headlight fitting.
You have to push the bulb and fitting HARD against the housing and then twist to actually seat the fitting into the housing. Maybe this helps... [?]
I just swapped out my headlights with LED bulbs tonight and the wiring won’t fit in the housing because of the giant plugs that came with the LED bulb (beamtech). My cover won’t fit because of the protruding cables so I left them off- I will let you know if anything happens. I assumed it’s going to be okay because there is a plastic ring that fastens the headlight to the housing and I am hoping the ring will act as a cover... then again, if it did Ford probably wouldn’t have made the covers. I will keep you updated- and if anyone here has a solution for my problem please link me or shoot me a reply.