I bought fiberglass replacements for my 1957 chevy pickup from Chevy Duty or LMC (forgot which). My main reason was that here in Minnesota we use a lot of salt on the road in the winter. This may offend some, but that was my choice. My fenders are OK, but they have required some amount of "wrestling" to get them to fit reasonably well. I'm not sure if my truck ever had a perfect seam anywhere though. Everyone that has ever looked at the truck, never realized they were fiberglass until I told them. I'm not dissatisfied, they look OK, but I'm not sure they will ever fit as well as a good set of metal fenders couold.