I've been slacking on the updates for this thread, but progress is being made. I'm going to add a few things in out of order to catch the thread up to where I'm at currently. So here goes.
The front fender is plastic, and the PO had it mounted without using the correct rubber shock mounts which resulted in a stress crack on the front portion. Their solution had been to sloppily rivet an aluminum plate as a brace to keep from further cracking.
I said "nay!" to this method, and proceeded to drill out the rivets and remove the plate.
After talking to irk for a while, I decided to go with West System's G/Flex epoxy system, which is a thickened 2 part resin + hardener system that is designed to have some flexibility when fully cured, making it perfect for plastic repairs. This stuff works absolutely fantastic.
First step was to channel out around the crack so I could get a decent bit of epoxy in there for the repair. I used a grinding wheel on the dremel tool while holding both sides of the fender secure. I kept it about 1/4"-3/16" wide so the epoxy wouldn't sag too much. The method to achieve best adhesion to plastic is to sand the surface with 80 grit sandpaper, clean, then flame polish with a propane torch. I cleaned with acetone after sanding (obviously, wait until the acetone is evaporated before you put a flame on it :
) and for the flame polish, you just want to barely touch the surface with the flame. It will go from a rough, dull surface to a nice shiny finish.
Before I epoxied the gap up, I cut a few strips of 6oz fiberglass cloth. I didn't take any photos of it, but before I filled the crack in, I wet out the strip on the back side so I would have some backing for the epoxy. I also added a 1.5" wide x 10" cloth strip going from front to back to add some rigidity to the fender. I used some scrap metal to prop the front half of the fender up ;D
After a 24 hour cure I sanded the excess down. Not bad and quite strong. My helper approves.
After a little bit of filler, a couple rounds of primer and wetsanding I got the fender and repair looking pretty darn good. I shot it with farm implement paint, installed the decals, then went back and cleared over it a couple weeks later. The orange peel on the clear is pretty bad, but I'm going to leave it as is for now - I may go back and cut and buff it later.
Once all that was done, I installed the correct rubber shock mounts and spacers to hopefully prevent any further damage in the future.