Everytime I think of Walnut blasting, I think of some sort of drink from Baskin Robbins...
Have you considered taking it to BMW Bellevue? There was a guy that posted his review of his Walnut Blasting done in August. That might be a little more convenient than flying Dr. Phuonger out here, unless you really really want him here. haha
-Thread for reference.
You might have seen it, but just letting you know just in case.