Very nice clean K20, congrats and welcome to the forum!
I'm running BFG All Terrain KOs in 33/12.50-16.5 so not much help..... but they also come in your size. You have a lot of great choices in your size. Most of us tend to recommend whatever we have spent our own money on, so I'll suggest BFGs, though they aren't cheap.
Grip that dome light lens top & bottom (centered) and gently squeeze, then pull it towards you to remove.