[felix_browne]

let me preface this by saying that my experience with fibreglass was limited to a few boat repairs and some small fitment issues on cars in the past. also, i may have just ended up with a bad pair of fenders but when I did my car I wanted the glass fenders to look like steel—like others had made theirs look. I spent more sundays cutting, sanding, reshaping and cleaning dried resin off my garage floor than I care to recall. I couldn't achieve my goal. they looked pretty damn good but there was just something about the thickness of the edges that didn't seem quite right. after glassing in steel headlight buckets, gas filler console and attaching a plastic shield underneath to stop errant rocks from ruining my new paint, they were only a few lbs lighter per side than the metal ones i ended up repairing the rust on and fitting up in half an afternoon.
I will not use glass fenders in the future.
as long as metal ones can still be had, unless you are building a racer, i would advise you to go that route. factor in your time and it will be cheaper.