I bought the rear fenders at the same time as the fender flares. If you did the same, install the fender liner FIRST! I was able to install them with my wheels, although that probably added to the installation time and made things a bit more difficult. But it can be done if you have a short (short) Phillips screwdriver. It took me exactly an hour to put them on at a casual pace. The hardest part was drilling the hole for the bottom screw. You have to get in from the back unless you remove the tire.