You don't have to resort to heavy chemicals to remove bug guts. Just park the truck on the lawn and turn on the sprinklers for an hour. That softens things up very nicely. But what works even better on surfaces that don't have much convolutions (this won't work on the grill, for example), is to lay a soaking wet old towel over the surface and go drink a cheap beer while the bug guts soften up. Then wash as usual.
It hasn't been mentioned here yet, so I will. Armor All is the slickest stuff you can coat anything with. Does snow stick to your snow shovel? Treat the shovel with Armor All and your sticky snow problem is solved. Works on bug guts, too. But there is a caution. I have been told that painted surfaces that have been exposed to Armor All cannot be reliably repainted. A body shop owner told me that, so I think there must be something to it. So be careful what you use Armor All on. It'll work on that plastic front grill like a champ, but it'll take some time to do it - gives you more time for another cheap beer.
