I have all four fiberglass fenders on my 53 3100. They were on the truck when I bought it, and they fit good, so I could give a rat's a$$ less that they are not "real" - but then neither are many other repro parts that I have put in the truck. Unless you are into show trucks that are all original, I don't see anything wrong with putting on fiberglass fenders.
Some of the vendors also sell repro metal fenders, but they are pretty pricey.
The Truck Shop
