You can install the tire wiper on the end of the fender. That would be my preferred option. Front fender - bolt to underside of fender, a bit back from the fender tip, so that the wiper part extends forward and just peeks out at the tip of the fender. Rear fender - bolt to chainstay bridge or to that end of the fender, so that the wiper part extends down toward the ground just aft of the BB.

Or, you can also install wider tire wipers that go around and under the fender. I think rootboy makes/made them.

Or, you can skip the tire wipers.