I got out to the garage and put some work into transfer seat. Here is the frame and the seat with the middle cut out of them.
So then I am talking to a friend and he comes up with the idea that I should simply remove the seat from the car and get rotating seat from a van that will simply bolt in there for when I am going to be taking him. It only happens a couple of times a year for the Goodguys. I can swap a seat in minutes! I am going to go over to the wrecking yard and see what they have there in the vans.