I would test this on a inconspicuos spot first.
I have had good luck with normal car wash solutions and a peice of oleifin indoor out door carpet as a scrubbie. The carpet can usally be found as a sample at the local HD or Lowes.
I soak the buggy area and using a wash sponge get as much off as possible. Then I use the carpet peice sopping wet and lightly scrub the bugs only trying to clean a small size spot, and making sure it stays wet.
WBCCI #5501 AIR # 49
1978 Argosy 28 foot Motorhome
Wise men talk because they have something to say; fools, because they have to say something. -- Plato