Camping with a cat

I take my cat in my 28 foot motor home. He's an indoor cat and doesn't even try to get out. At first I got a large wire crate and strapped it in by the passenger seat. Put a nice soft rug and his bed in it. When driving, he yowled constantly and would stick his paws through the wire reaching for me. I tried covering the cage so it would be like a cave (he likes to burrow.) He yowled constantly, amazing what volume a cat can have. When I would stop at a campground and let him out, he was perfectly normal. He even went into the open crate to stretch out and snooze. Finally during a long noisy drive I stopped at a rest stop and let him out for some food and water. He stretched out on the dinette cushion totally relaxed. Back in the cage - YOWL. I couldn't take it anymore. I stopped, let him out and said this is it, your choice, if I get in a wreck you know you're toast. When I started the engine he went in the back and burrowed under the bed covers. When I stopped for the night, he strolled out and stretched out on the dash. That's now our routine. When I get ready to leave I put him in the bathroom until the slides have finished moving. When I start the engine he burrows under the covers and sleeps until we stop.