The odds of being stopped if you don't drive like an idiot are very low. The odds of a search if you get stopped are also very low. Multiply the two (they don't get added), and you have a risk level that is hard to express, it is so small. They are also unlikely to be looking for gun; the N/S highways in Illinois (39/55/57) are major drug thoroughfares and that is out of what they seek.
I set the cruise at 65 and hide in the right lane. It's the only way I can get 10mpg. I'm sure we'll be fine.
T4