zosomoso

Im surprised no one has asked this yet but have you tried a clay bar? Does the surface look kinda matt or sanded down black ish? chances are that it has not eaten through your paint. i had a similar bird poop incident on my black 350z and since all the birds in my yard eat highly acidic berries from our cherry blossoms believe me it was as harsh a stain as it gets. i tried everything; waxing, orbital buffer, stain removers (dont recommend any of those).. etc. last but not least i purchased a claybar from the guys at Zaino. Using it correctly it took me about 5 minutes, and revealed a brand spanken new shiny surface underneath, i was shocked. after so much effort before yeilding minimal results this was just too good to be true.

good luck and dont lose your head over it, i almost did
Darius