Spirithorse:
This is a complicated form of compound cut with resulting parts (the fenders) that are not symmetrical. If you have not done compound cuts before, you might start with something like the Christmas Tree Icicle ornaments in the Holiday issue of Woodworking & Crafts to get a feel for them. They are pretty amazing when you unwrap them.
Here's a side view of the prototype:
Here's a top view (glue was still setting at the time):
A compound cut uses 2 cuts to get a 3-dimensional shape. We are making multiple compound cuts to get (1) the 3D body, (2) the 3D left fender, and (3) the 3D right fender. I started with a blank cut from a piece of pine 2x4, 1.5" x 3" x 7.5".
After drilling for the axles, the 1st cut gives the side view of the body; looking from the top, it still looks like a 3"x7.5" rectangle. My saw (EX-21) is not big enough to cut through the 3 inch dimension so I did that cut on a bandsaw.
2nd cut is the top view of the body and strips off the 2 fenders. The body rought shape is done. But at this point, if we look at the fenders from the side, they will be the same shape as the body side view. So they each need another cut.
3rd cut is to get the side view of the left fender. That makes the 2 cuts to get the compound shape of the left fender. This is tricky because you can't reassemble the full blank to make that cut (because you would wreck the body part). One way to simplify it might be to start with 2 original blanks, make the 1st & 2nd cuts on both, then sacrifice the body of the 2nd blank to help cut the fenders for use on the 1st body. I did not do that and as a result got some rough cutting as seen in the photo.
Forth cut is the side view of right fender.
Since we cut the fenders from the same blank as the body, the fenders should be able to glue right back onto the body. You might test-fit them, then do some shaping with a sander to get them closer to the desired overall shape.
A Morgan enthusiast, or a detailed modeler, may not be satisfied with what I show here - it is not smoothly finished, or include details like seats, headlights, bumpers, etc. It is the way I like toys - looking more like a sketch than a photograph, simple to make and to fix if a happy hooligan rolls it down the steps. But probably not meant to be mounted in a showcase. That detailed finishing takes the bulk of the work, and if it's what you like to do then have at it.
I hope this answers your questions. If not, let me know how else I can help.