Ok, so I have been battling issues with an aftermarket stereo install that does not agree with the Clarity's active noice cancellation system. So found myself in need of going into the dash to disable the ANC module. Since I was already half way there, decided (with the help of the 3986 guide) to go in and really clean the instrument cluster lens as mine was one with factory "whatever" on the inside. Honestly looked like it had been wiped down with a sweaty rag inside. However, keep in mind that you could only see the grunge when the sunlight hit at an angle from behind, if the gauges were in the shadow of the eyelid, you couldn't see anything. Never even noticed on my test drive.
So, removed the visor and cleaned the plastic (acrylic etc) lens carefully. I would note that they did a poor job in polishing the plastic as it has swirls in it from the factory that you may get out with a cleaner wax/carnuba polish, but at some point you have to just stop. I wanted the smudges off the backside and that is what I accomplished. This is not a hard project and can be done in under half an hour. The reason I didn't take it to the dealer is that they would likely not clean it, only replace it, and if the tech is not careful (like an owner would be) you stand a chance of gaining nothing. That and it takes a lot of time going to the dealer, this was a 30 minute project, even having to figure it all out. Here are the photos, everything except taking the lens off was easy (the lens requires a lot of snaps be carefully unlatch, you don't want to break them or crack the plastic). Honestly the best tools were tools you would get to replace a phone screen and are super cheap (spudgers, plastic pry clips, and suction cups, ie :
http://a.co/d/3ApdpEq but I had a lot of this kind of stuff so this is only an example, didn't order it.
I'm a pilot, so I used stuff I use to clean very expensive plane acrylic with and trust.
http://dwdavies.com/product/klear-to-land Use whatever you want but make sure it is not alcohol or ammonia as it can craze the plastic and I don't know what kind of plastic it really is. Davies is just easy as it has more MIL specs for acrylics than any normal consumer product so I didn't have to worry.
Once it is removed, clean it carefully, use canned air to blow dust out of the cluster area, and re-install. It was easy. The foe wood trim is kinda a trick to remove. You pry up (with plastic trim tools) the front, then pull it out at a slight (say 15-20 degree up) and back angle. They are not straight in or up, kinda an angle.
Photos attached when I get the downloaded. Will update tonight, sorry - wife calling...