The old saying goes you pay for what you get . Being a black car you,ll always gonna see more defects than lighter ones . I would clay the surface 1st before any polishing commences . Lots of do,s and donts when it comes machine polishing , things like pad selection type of paint , technique etc etc . G3 is a cutting compound your gonna want something more refined than that . There,s so much too it , have you gone on DetailingWorld . Very useful guides on there .

Mike