Biggest non-slide campers?

The AF 865 is 9ft 4" very nice non slide camper.

Apache Camping Center in Everett, WA, Tacoma, WA and Portland, OR has the Arctic Fox 865. It's the only non slide AF, and Apache is the only dealer that carries it.
It's a tad longer than the 811, but not huge by any means.

Thanks all - I'll pass those ideas along!

If they don't have 18" of clearance, just open the slide less

There aren't a lot of new and long nonslide models, but look at Bigfoot, Northern Lite, Adventurer, and S&S. You might need to look at a few year old models.

The wife and I took a tour of the R.C. Willett Co., Inc. (Northstar) at Cedar Falls, IA while attending the 2nd Annual Mid-West Truck Camper Rally at the Amana Colonies two weeks ago today. Rex hosted the tour and showed us an eleven foot non slide model that will be in production soon and is taking orders from prospective buyers now. This thing was huge and will be an awesome looking hard sided camper when it leaves the factory. I was really impressed with it as Rex said it would go on a three quarter ton crew cab long bed truck with no problem. It was amazing to see how these campers are made as I have never toured a factory like this before.