I started with the front wheels first. Simply power up the car and turn the wheels in the direction of the side you’re going to install.

You first need to remove the bottom two pushclips. Note the 2 slots on the base of the clips.

The easiest way to remove the clips is to find a flatblade screwdriver that fits the slots, push it into the slot until it slips under the center piece, then twist the screwdriver. Once the center has popped up, simply grab it with your fingers and pull the pushclip out. You will not be reusing these pushclips, so store them somewhere in case you need them in the future.

Next you need to pull the plastic shield away from the fender...

...so that you can install two spring clips (and clean out any leaves you find in there).

Next, line up the splashguard with the two holes where the push clips used to be, and insert two metal screws into the holes and spring clips. As you tighten down the two screws, gently push the splashguard against the car so that it makes a tight fit.

Next, drill a 6mm hole through the plastic wheelwell shield. If you don't have a 6mm (0.23622") bit, you can use:

Bit size		Decimal size
1/4"		0.25"
15/64"		0.234375"
A		0.2340"
B		0.2380"

Once the hole is drilled and you have cleaned off the plastic bits, insert the pushclip provided.

First you need to block the front wheels (Although the vehicle is in park, I still urge you to block the wheels). Next, loosen the lug nuts on the rear tires slightly. I used a 4-way lug wrench. The lug nuts are 21mm. Then jack up the car.

If you’re lucky enough to have a floor jack, make sure you use the center jacking point. If you’re going to use the jack provided with the Prius, make sure you read the manual so you jack the vehicle up in the correct way.

Once the wheel is removed, you’ll have plenty of working space. Hold the rear splashguard up to the body and using a 6mm bit, drill the top two holes. If you don't have a 6mm (0.23622") bit, you can use:

Bit size		Decimal size
1/4"		0.25"
15/64"		0.234375"
A		0.2340"
B		0.2380"

What I did was drill the top hole and insert the springclip...

Then loosely screw in the top screw to help hold the top of the splashguard in place while I drilled the second hole. Add the springclip for that hole, hold the splashguard tight to the fender, and tighten the 2 screws down.

For the third screw, use a 2.5mm bit and drill the bottom hole, then insert the metal screw (Do not, do not, do NOT drill a 6mm/¼" hole here, it will be way too big!!!). If you don't have a 2.5mm (0.0984") bit, you can use:

Bit size		Decimal size
3/32"		0.09375"
#40		0.0980"
#39		0.0990"

At this point, you can replace the tire, snug the lugnuts down, and one side is done. Repeat for the other side.

But if you're Mr. Overkill like me, you'll see that the end of the rear splashguards is pretty loose, so you'll find another screw similar in size to the ones with the kit, and drill another 2.5mm hole here. Again, the drill will be going through 2 plastic surfaces, so you don't have to push hard - let the bit do all the work.

Here it is fastened down with an extra screw.

Rear view of the rear splashguard.

Finally, torque your lug nuts down (76 ft-lb). If you don’t have a torque wrench, make sure the lug nuts are tight and try to ensure each one is only as tight as the others. Use a "star" pattern when tightening.