I agree, you need at a minimum to get the axle weights from a cat scale. There is one in Havre De Grace MD that I am aware of at truck stop. ( see your from Md)
We just got a new coach last month and it was wandering a bit and a little rough. Was running at max psi from dealer 120psi. Had coach weighed fully loaded and was several thousand under max weight for each axle and was safely able to lower the front from 120 to 90 and the rear from 120 to 95 and this is still with at least a 5 psi buffer.
Made a huge difference in ride. If 83 is your max and you have a light coach, I'm sure you could probably come down more than 5 psi. However I wouldn't do it until I had the supporting evidence from the scale.
Good luck!