the bear II wrote:
Here's what we had when towing a TT.
I had a campershell (cap) put on the truck with a pass through Boot between the back window of the cab and the front window of the campershell.
I attached a 4 foot wide one inch thick piece of plywood long enough to fit from side to side on the campershell lip/ bed rail. I placed 2 inch foam rubber on the plywood and covered it with indoor outdoor carpet. This provided a bed for the two dogs. They used to lay there and look out the through the pass through as we drove down the road.
The air from the dash A/C kept them cool and they could walk around on the bed. I kept a non-spill water dish on the bed in the corner.
This! This is likely your simplest and least expensive option.
Now as for the dogs riding in the TT, they are dogs, dogs are adaptive creatures and will find a comfortable spot in the TT, as long as the temps are decent they will be fine. Have you thought about crating them in TT? That would minimize the movement of the dogs.