Hillguy
Unless you have written proof or a link to a post made by someone actually from Evga then you are making assumptions based on your opinion which will not help anyone if they have an rma issue from discolored lights.  The fact you say it's reversible is based on your abilities to clean. I'm just saying what "If" someone in the rma dept sees traces of the yellow or red or whatever color is used ?? How do you prove it's not a drop of spilled water from a poorly installed water block ?  I know it sounds picky ( and this is Evga where rma's and customer service are beyond reproach ) I'm not saying you are wrong or that they can't be cleaned but that's an expensive card and I would do nothing without "Official" notice.  Just my 
 
Maybe the best course of action might be to start a thread for owners and see if Evga might make a small lexan cover or something for it ...  who knows they just might make one

By US law they would have to prove that the colored lights were the cause of a catastrophic gpu or board failure before they could void warranty...........I mean, again.....lets USE common sense.......you can literally take apart your EVGA video card and retim it without voiding the warranty........so you really think coloring a few accessory led bulbs is going to void anything?