The rivets definitely break. Make sure you buy a rivet tool, it will make the installation a breeze. There are clips that mount the fender to the body...most of the time they can be saved (I think I broke two when I replaced all four). When you get the fenders off and go to re-attach make sure the clips are on the fender flares and press the fender flare onto the body. When I took my old flares off most clips stayed on the body not on the flares.....so I put all the clips on the body and tried to attach the flare to them......very frustrating.....so clips to flare first. Hope this helps. Took me less than an hour.
I used clipsandfastners.com