T'ondaB'. I use to do a lot of auto reconditioning, and here is a tip that will work.
We used this on the clear-coat also to get rid of acid rain and mineral spots on
the paint. Take one cup of white distilled vinegar to one cup distilled water and
mix. Take a sponge, soak it in this solution and liberally apply to the surface that
you are trying to remove the spots from. Let it soak, (re-application may be
necessary), wipe dry and lightly polish by hand to see your progress. Another
application may be necessary depending on the severity of the water spots,
or "etching" as we use to call it, since the acid rain and such can literally
etch your paint and glass.