I'm on the brink of doing this myself, and this is the most comprehensive instruction i've received originating from Ed Villela.
(Tom, Wayne, DD, or Don, you guys there?.. might want to ask Ed if he wants to write an official copy for the tech articles)
anyways, here it is..
>First thing to do is to cleann the
flaresand fender with a good wax and
>grease remover. Then wash with warm soapy water. Now fit the
>correct fenders. It helps to have an extra set of hands here. Hold the
>flare tightly to the fender and check for fit .Adjust it so that it is even
>on both sides of the wheel well opening. Now take an 1/8-in drill and drill
>a hole in the top center of the flare, approximately 1/4-in in from the
>outer edge. Now insert a self tapping sheet metal srew in the hole. Do the
>same every 6 to 8-inches apart as you work your way out towards the bottoms
>of the fenders. I like to use the sheet metal screws with the hex heads,
>1/4-in I think. I use a cordless drill or a nut driver to insert these.
>Look for gaps between the body and the flare. Take a black marker and
>highlite the low areas, where you can see a gap in between the flare and
>the body. High lite the whole low area. Do this to all the low areas.
>Remove the flare and take a sanding block with 80 grit sandparper and
>slowly remove material on both side of the low area, then re fit the flare
>to the fender and check the gaps. If the gaps are less than a 1/16th of an
>inch you can stop, thats close enough. You want the flare to fit as
>tightly to the body as possible.
>Now take a scribe and outline the edge of the flare into paint on the
>fender. Remove the flare. Now follow the inside edge of the scribe with a
>strip of 3/4-in masking tape. Now follow the inside edge of the masking
>tape with another strip of 3/4-in masking tape. This will give you a 1 1/2
>-in border inside the scribe mark. This will be your cut line. The 1 1/2-in
>border will be used as your bonding area. You may need to trim this area
>down to a 1-in border.
>You can cut the fender out with a jig saw with a metal blade or metal
>nibblers. Follow the edge of the tape. Once the cut is completed, take a
>grinder and remove all of the paint in and around the bonding area. Clean
>bare metal is important here. Also grind the back side of the flare to
>rough up the surface. This will ensure a good bond with the
>resin. Re-fit the flare. Look on the inside of the wheel well, is the
>metal sitting flush against the back of the flare? If not push or tap it up
>with a hammer until it is as close as it can get to the back of the flare.
>Next drill holes in between the existing srews , all the screws holes
>should be approximately 1 to 1 1/2 inches apart. The entire outer edge of
>the flare should have screws holes in it. Now remove the flare.
>Okay, we're ready to bond the flare on. Use
FiberglassJelly Resin for
>this. Mix the
fiberglassjelly and spread it onto the back edge of the
>flare. Put on a liberal coat, do the same to the fenders edge. You need to
>work quickly, you want to get the flare fit before the resin starts to set
>up. Now put your screws back in and put screws into the new holes that you
>drilled. A cordless drill with a nut driver works well for this. Screw the
>flare down tightly. Wipe away excess
fiberglassresin. Let this set up and
>dry at least 24 hrs.
>When the resin is good and dry, remove the screws. Take a grinder and grind
>down the edge of the flare, blending it into the metal. Also grind down the
>area where the screw holes are.
>Spread a coat of
fiberglassreinforced filler over the screw holes and seam
>where the flare meets the body. Press the filler into the metal and the
>flare to ensure a good bond. Let this dry and then cut it down slightly
>with a cheese grater. Now apply a coat of regular body filler over this and
>blend it into the body. It helps to use curved sanding blocks here. I use
>wooden dowels of various diameters wrapped with sand paper to cut and shape
>the inside curve areas.
>Fill and sand until all the curves feel smooth and flat.
>Prime with a good filling primer, block sand smooth and then paint body
>If these steps are followed correctly, the
flareswill be very rigid and
>will not crack and separate from the body.