A roll-back deck would really make it easier to get the car on & off. (If there is one, I couldn't see it in the photos.)
EDIT:
I think I recall seeing a picture of one built from that motor home that was based on the Olds Toronado drive train. That allowed a much lower center of gravity for where the car sits.
I wish I had some progress to show... Unfortunately, life and other projects have stood in the way. My plans are to try a roll back of some kind. Am thinking hydraulic dump with winch style roll back....just haven't made a good start. I was looking hard the other day at removing the 46 cab but man the heat is killer right now and I only have an area outside large enough to hoist the cab off with my big A-frame. About 15 minutes into any project here right now and you feel 10 lbs heavier if for nothing but wet, sweaty clothes.