i wanted to do this, but after talking to some people, i decided not too. they told me that if you plan on driving it a lot on the street, the stones will hit against the panels and dent them up. so my second plan was to use a light gauge sheet metal and paint the black or the body color, whcih would hold up a little better. i took a big piece of cardboard and laid out a pattern, with all the cuts, and the angles, and was getting ready to go get the metal, and for some stupid reason, i decided to put back the factory inner fenders. i was having problems deciding how to mount the panels, to the fenders, and also be able to remove them, if needed. i wanted to use dzus clips, but it started to be too much, so i scrapped the idea.
if you have access to a shear, and brake, and bead roller, you can do a nice job.