Nice work. You spare me much time, but thus i remain without learning knowledge about extracting for this.
But there is strange thing, may be i do something wrong.
I tested several models, every try import as obj into 3dmax8 ended crash max. Import into imdeditor works, but on models with more parts is material missing. Import into blender works, again material is missing. Material can be set manualy here, but i still have no knowledge for this.
My way for blender, there exists simpler ways for shure too
I imported all obj for required model from directory and reexported as new obj.
This can be imported into 3dmax yet, there can be material defined. Or manualy editing file "model".mtl allows set materials too and then import into imdeditor shows all materials.
Some parts with identical material can be joined into main body for simplify.