Just curious, did you ever find a solution here? I have a spacer installed, around 1.5" and get this same clunk/loose feeling when hitting bumps. Toyota recommended upgrading to the 5100s but I'm afraid this won't fix the issue. Going no lift might be the only option.
Pre & Post 3/4" spacer (1.5" lift) up front on a 2015 Trail KDSS. Came out almost exactly level, the rear being about an inch higher still. Measurements of body have it exactly level, no negative rake at all!
I worked something up on the computer at first but remember cutting and measuring on the go. I can get you the solidworks (CAD) file if you want and you can download the free viewer (edrawings) to take measurements. I'd be measuring on the go those if I was you. I wanted a tight fit and there...