The Ridge-Rest pads did not work out that well, as the north-south ribbing on the bottom of the camper does not match up well with the bed of the truck. So the camper was only sitting on the truck in a few small places, and the focused weight crushed the foam pad.
I will edit that post to indicate this.
Here is what I am doing now. (This spring I used the camper with no pad under it. It worked fine, but I would like to find a thin pad to go between the camper and the truck bed.)
First project was to add wood strips to the bottom of the camper. I am doing this because I did not want to use the factory supplied bed mat because it was so heavy. And I also discovered that the runners on the bottom of the camper did not match up well with the grooves in the truck bed, as both ran north-south, so the camper was only sitting on the truck bed in a couple small areas. So some runners going east-west were in order.
At some point in the future I plan on putting another coat of stain on the bottom plywood of the camper. I feel that with all the holes I have drilled it would not be a bad idea, and the factory stain is a little thin in places.