I've put the rear liners in 2 different 2023 silverado 2500hd's. There really isn't an "easy' way. It's best to remove both guards "front and rear" on the wheel well. Started by putting the front of the liner behind the lip on the front and worked back to the rear pushing back toward the inside. I was able to get a one hole in the inside above the tire lined up and pushed a keeper part way in. This held the liner up and in place while I worked the liner in, along the outside rim, using screwdrivers and small pry bars etc. As some of the holes lined up I partially installed more keepers. The real challenge is when you get to the bottom rear, and pry the liner up and over the rear lip where the mud flap screws on. I think it would be easier with the wheel removed but I was successful without doing that.