Wet sand 1000 grit, then 1500 grit, then 2000 grit. Hit the spots with rubbing compound, then polishing compound to remove any swirls, then finish off with high end polish. 3M makes the best compounds and polishes. You may have to Buff a few times depending on how easily the spray paint comes off. Just a tip, don't use force when wet sanding, If you can get a block use that and let the block do the work. The last thing you want to do is force it and blast through the clear
I don't have the car now but when my new 2005 GTO came in to the dealership GM had repainted a place on the back bumper when it got off the ship in California. And of course they can legally do that and not disclose it even thou it was sold. And you couldn't see it (bright blue car) but you could feel rough over spray about half way up both quarter panels and back of trunk lid. I took it to a body shop and they simply took enamel reducer and gently wiped without rubbing and it took it right off. They did have to put new tail lights in since the reducer will etch the plastic. GM paid the bill but I was still pissed to wait 5 months for a car from Australia and have damage repair and not disclose it.