I followed the example of others, and made a platform for our two dogs.
The impetus for this was a recent trip. Up until today, we always folded up the seats and put their dog beds on the floor. But I’m this trip, I realized it’d be nice for the dogs to see out the window(at least Addie, pictured here; the other one is a little pipsqueak). It also be nice to have some interior storage. This accomplishes both.
The platform dimensions are 60x30.5”, and this worked out perfectly. At the front and back of the platform are 2x4s, 56” long. This adds stiffness, and also keeps the platform level at the back of the seat. The legs at 12 5/8” long, and installed with hinges on top of the front 2x4.
The platform is 19/32” plywood. I could have saved money and weight with thinner plywood. I was concerned it wouldn’t be stiff enough, but that was before I got the idea for the front and back 2x4s, so if I were to do it over, I would go thinner.
I used both carpet and carpet padding to make the platform more comfortable for the dogs. For road trips, we’ll still bring their beds, but this is fine for short trips to the park, vet, etc.
I will probably wrap the legs in carpet for aesthetic reasons