just my first thought.
try placing a 1 to 2 board under the right rear tire to level and thus put more weight on the left and see if that lowers it.
I think the front on a center jack is an unknown as to how the weight is suspended. making sure it is a "free pivot" and moving it over to the right.
do you have the spring lenghts free and then mounted.
any way to test the rate
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