Generally, even if it is a fiberglass body, fenders and other items like running boards have flanges on them where you have to drill holes and run bolts through to afix them. Sometimes you insert welt between the two to act as a dress up and also insulator. (I've never owned a car with fenders, so I have not done this personally )

While buying someone elses half finished project can be a great way to get a good start and save some money, the one drawback is you sort of have to start without a clear picture of what you have to do to finish it. You just have to start holding things like fenders up against the body and mocking up the car, then you can see what needs to be done to bolt them on. Loosely tape parts on and block them up until you are sure they fit before you start drilling holes. All parts, whether they are glass or steel require a certain amount of finesing to get them to fit properly, and sometimes this can require some compromises just to get them to fit reasonably well.

Most of the knowledge you need will come from just sitting down and studying your car and seeing what looks right.


Don