Hi,
I would relocate the spare tire to get the lift as close as possible to the front of the trailer. This will bring the weight forward as much as possible. Right now you are putting about 350 pounds about 4 feet behind the center of the rear axle, and this can transfer more than the total hitch weight to the rear axle, leaving the hitch sticking up in the air (very dangerous).
Without a minimum of about 300 pounds of hitch weight, the trailer will become very unstable while towing. If your hitch weight before installing anything is about 250 pounds you need to keep it around that weight once completed, and make sure that it is not lighter.
Moving the spare tire to the front of the RV will help, but probably not enough to return the RV back to a stable towing trailer.
You might also need to remove the chair batteries, and move then to the front of the trailer, IF the trailer does not have enough hitch weight. I had to do that when I carried a 350 pound 2 passenger scooter with a Jeep Limited. The front axle of the Jeep was getting light when the batteries where in the scooter, so I had to remove the seat, then batteries, then put the seat back before towing it with a large DP.
Good luck!
Fred.
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