2015 Arctic Cat M8000 throttle preventing RPM above 3500

I purchased a used 2015 AC m8000 snopro this season. The first 2 trips out it ran great but on the 3rd trip it did not want to go above 3500 RPM. I remembered from an AC that I owned years ago that pin holding the throttle had worn and was causing a similar issue so I tried pushing the throttle from the bottom instead of the top and the engine revved fine. I think the fix I used on my previous machine was to add an additional nylon washer(s) between the throttle lever and the assembly that attached to the handlebar.

Is this the best fix for the new machines? Other fixes?

Hopefully I'm not repeating another thread already on the forum, I couldn't find anything.

Thanks in advance for your help!

2015 Arctic Cat M8000 throttle preventing RPM above 3500