[GrumpyShihTzu]

The stock mudflaps should be held in place by plastic clips similar to these 30pcs Plastic Rivet Fastener Bumper Clip Push Retainer Screw Fender for Nissan | eBay and maybe a screw. Remove the clips and take one to the hardware store and try to find a screw that will screw into the clip. Once you find the screw, then look for a washer that will fit the screw. Make sure both items are stainless steel because they're going to be exposed to the elements. Then line up the mudflaps to your liking, mark the holes that you need to drill, and drill the holes. It's easier if you stack the front flaps on top of each other when you drill them. That way you know that the holes are going to be even and in the same spot. Repeat for the rear flaps. Insert the stock clips back into their place, then hold the flap in front of the holes and insert the screw with the washer over it. On the driver side front, turn the steering wheel all the way to the left. This will give you enough room to fit a screw driver. Then repeat for the other side. For the rears, I suggest using a rachet with a phillips or flat head (depending on which screws you bought). You also have the option of taking the wheels off. If you want pictures, I can take some pictures of my Rokblokz and show you how it's suppose to look like when it's installed when I get off work.