All bent edges (inner profile) needs to be rounded/filleted ~R2 mm.

Also the inner profile of the fender is curved in UVN directions (that is, no flat surfaces whatsoever).

Most curvatures seems to be changing radius gradually.

The headlight area is also flattened (around the hole the surface is flattened about 5-10 mm radially).

The flattened inner top profile is leveled (along the length) as it’s aligned with the hood/bonnet which has a flat bottom edge.

This highest point extends as a softly rounded ridge along the entire length of the fender.

lowered & flattened towards the inner profile (the front part between the fenders also has a flat top surface seen from the front).

The shape on the highest point is rounded towards the top and outside (kind of “circling the head lights”), but it doesn’t go straight towards the inner profile, or upwards, instead it is ….

Q: What approach/workflow for shaping this kind of fender would you guys suggest? I tried searching for tutorials for this kind of shape, but since this is not exactly “free” form (as with any car body part) it needs to stay within some dimensions, and have the exact right looks at the end of the day). I don’t have any drawings for this fender, but the pictures below should at least illustrate the difficulty.

Below an arbitrary example fender (but quite tricky shape, I think) for which I’d like to learn the appropriate tricks. I’ve tried creating some “modern” body shapes for cars, including fenders of course, but very curvy fenders for older cars seems to be trickier.

Autodesk memento model extrusion