The most possible to do that is to edit the 3d model of the high socks. By doing this, you need: Blender(any version) and 3DM Mod tool.
1: You need to Open the global.iff with the 3dm mod tool.
2: Then find for the following body types: Normal = "4A610FDA", Fat = "7DA47411", Slim = "537BA67B", and Athletic = "E9B23D51".
3: You have to edit the 3d model of the high socks from every body models but I will just demonstrate one body model.
4: So export the body model from the 3dm mod tool and import it to blender.
5: Look for "0-58" (Right leg) and "0-26" (Left leg)
6: Resize it using scale (Hotkey "s") or grab (Hotkey "g") and drag. Do whatever you like with the model.
7: If your done with it, export the model from blender, (make sure you are in "Object mode" not in "Edit Mode" or "Texture mode" because it will cause error when you import it in mod tool.
8: Import it in the global.iff using 3dm mod tool.
9: You're done. check in game.
Mind to check out my page here:
https://web.facebook.com/Dann2kMods I mod cyberfaces, globals, audio, jersey, floor, callnames, and in progress with custom commentary.