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I found a good weapon is those little flossing brushes like mini pipecleaners. The mealybugs were living on my orchid between leaf and stem where they couldn't be reached without damaging the plant. I've found with regular inspection and extracting any bugs I find, they're not totally gone but they're occasional only. Also I didn't realise until recently that the males look just like other tiny flies, so kill those as much as you can too.
I've done this. I've done it heaps of times and the fuckers still get everywhere.
I had the world's biggest zygo (it flowers twice!) And they have wrecked it. My massive money plant is a write off too.