i get that same felling every time i take somthing apart.
i get so freaked out that something is broken.
just changing the strings makes me nervous...
well not really
truss rod cover you can buy for like 2 $
nothing to worry about
and the corrosion, i have that all over my tremolo.
its just the finish coming off the metal parts.
just looks uglier , doesnt affect your playing.
unless its rust!