Many years ago some kids were doing "drive-by spray paint" on light colored cars; mostly white ones. My white pickup parked on the street got hit. My neighbors made insurance claims and took their vehicles to the paint shop. I bought a jug of degreaser/bug remover from the auto parts store. An hour of scrubbing and I was good.
My point is to not only tell the story but to suggest that probably most of that type of product at the auto parts store, regardless of brand, will work on bugs.
The po-po caught the kids, BTW.