You may be able to import the .obj into your modeling software and assign matrials, and then re-save it so that you can select by matrerial. And/or you may be able to name each part and re-save it. I name my parts in Nendo then when I load the model in UVMapper I can select by group and they each have meaningful names. Don't know if you can do that in other modelers or not, but I suspect you can. jon

 
~jon
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