Fine tuning Equilizer hitch

I am in the process of fine tuning my equalizer.I found after you get it close the last adjustment will come on how it feels when you are towing. I towed my trailer last week to a campground an hour away. The truck and the trailer felt good. I found the steering felt easy and I had to pay attention and keep two hands on the wheel all the time to keep ahead of any sway. After the trip I added another factory washer.It was to much of an adjustment. I could tell because the steering was a little to hard. The bars were making to much noise, not just on backing. There was noise on making regular slow speed turns. I decided to try adding a fender washer with is about half the thickness of a factory washer. I did have to modify it. I had to make the inner hole bigger with a step bit. I installed it in between the factory washers. ( I have 5 factory washers installed) I test drove the rig and I think I have it adjusted properly. The steering was a little tighter and I could drive with one hand if necessary. It also felt better at 65 miles an hour. There is a big difference between a factory washer and a fender washer adjustment. The factory told me a one hole adjustment on the L brackets is about the equivalent to a two washer adjustment. My measurements on front fender is as follows, uncoupled 35",coupled no WD 35 3/4",coupled with WD attached 35 5/16. I have a 2004 GMC Yukon towing a Skyline Koala 26SS. I tow in 3rd gear with my tow haul on.