My sunroof on my 04 E46 took a crap on me - plastic worm gear track broke so decided to replace it with one from a donor car. The front metal spring on the sunshade - both mine & donor, passenger side was broke. I have one good one from the donor. Can these be replaced? How? The donor shade is toast so have to use mine. Also, can the sunshade be put back after the sunroof is installed? Thanks for all help.