I use 3M's trizac 3000 grit on a DA with a hint of water spritzed on the paper, run low speed .
then use 3M's compound and polish.
beings its lacquer it wont take much to sand through it, as its not as heavy body like the new High solid Acryilc Ureathane Clears.
Did you water sand it flat after 4 coats of clear then spray 3 more coats of clear again? as this helps on having NO paint edges from the stripes when sanded and buffed.

http://products3.3m.com/catalog/us/e...er/output_html

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