STL Color Zoning Edits

I have a set of finished STL models created in Meshy that now need precise colour zoning. For each file I will provide a marked-up reference image showing exactly which faces go to which palette; every model needs just two to three distinct colours.

Your task is to:

• Apply the specified colours to the correct regions without changing geometry, scale, or vertex count.
• Keep the master file in STL; if you must convert to OBJ/3MF for colour work, include both the working file and the final STL.
• Send back a quick viewport render or screenshot so I can verify the palette before approving.

The colours must display properly when I reopen the files in Blender, and boundaries should follow the contours cleanly—no bleeding or jagged transitions. One-day turnaround per model is ideal, and clear naming of versions will help me track edits.