The area you're headed is going to be chock full of massive amounts of bugs. I'd focus on that problem and not worry about the vehicle getting dirty. Especially, since it is black. Deal with the car being a little dirty and wait until you can get it home and do a proper wash without the danger of swirling up the paint.
I'd pack a bottle of bug remover, a bottle of QD spray, and a healthy number of MF towels. You'll need both to de-bug the front of the vehicle. When we travel, I typically hit the front and side mirrors with the bug remover, wipe it off and most of the bug splatter. I'll then follow up with the QD spray.
As for glass cleaner, I don't bother. I've found the washer solution most gas stations provide in the buckets has some pretty good stuff in it. Not only that, but the "scrubber" side of the squeegee is really effective at removing splatter from the glass. I consistently clean the windshield at EVERY gas fill up to make sure the glass is always as clean as possible. On one of our most recent trips across Missouri and Oklahoma, the bugs were so bad I had to make an extra stop to only clean the glass. The mess was so bad I couldn't see out the windshield in the evening light/darkness.