was it done in clear coat base coat?i would have the body shop do the wet sand buffing . my cousin had his 70 plum crazy cuda repainted i watched the painter do the wet sand then buff it turned the paint job into a mirror finish
u dont have to find a donner car cut the rusted parts away form new steel into the hole u can use bondo or glass to cover the patch .but cutting the rust out is the only way to fix it ! DON'T CUT CORNERS HERE ITS A SAFTY THING!