I was looking for a solution to this and stumbled upon your thread in the official forum. Here's what I could collect by looking at official forum posts and the Farseer source code:
When using the factory body, the width / height / radius parameters are supplied to calculate the moment of inertia. The body class itself has no fields or width and height properties.
I think what you are looking for is how to resize the geometry, which is important in collision detection.
Geom (, ) //. , . geom :
public void SetVertices(Vertices vertices)
{
vertices.ForceCounterClockWiseOrder();
localVertices = new Vertices(vertices);
worldVertices = new Vertices(vertices);
AABB.Update(ref vertices);
}
. , , .