I have done a few bears the same way with good results. Use commercial hydrogen peroxide and the whitening paste to finish it. I use plastic wrap after I use the paste and peroxide and leave it outside in the heat. Before whitening, I soak my skulls in acetone. I think it's better than dawn. I did a write up not too long ago. Of course all the photo bucket pictures are gone.

https://www.24hourcampfire.com/ubbthreads/ubbthreads.php/topics/12065481/bear-skulls#Post12065481

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