Rectangular Watch Case 3D Redesign

I’m shifting an existing round-dial watch case to a sleek rectangular format and need a solid 3D CAD model that preserves all internal clearances from the supplied STL while upgrading the exterior look.

Here’s the scope I’d like you to follow:

• Base model: You’ll receive the current round-dial STL so you can match wall thicknesses, lug positions and the gasket channel exactly.
• Shape change: Re-engineer the geometry into a rectangular outline with harmonious proportions—nothing feels stretched or squashed.
• New styling: Add tasteful engravings or patterns to the case body (I’ll forward reference images) and apply a contrasting surface finish so the watch reads as a premium piece when rendered or printed.
• File delivery: Please send the editable source file (Fusion 360, SolidWorks, or Rhino are fine) plus a watertight, print-ready STL.

Acceptance check
1. Dimensional fidelity: internal seating for movement, crown tube and screws must match the round case tolerances.
2. Visuals: at least two high-quality renders showing the engraving detail and finish contrast.
3. Manufacturing readiness: STL passes MeshMixer/Netfabb inspection with zero non-manifold edges.

If you have creative ideas that push the design further, I’m open to seeing quick sketches before final modeling.