The one time I had mites from snake sitting a friends snake it was the most annoying battle ever. It was something like 4 years ago, but I treated everything twice a week for three weeks(giving the eggs time to hatch if they weren't killed). I cleaned all enclosures with bleach and wiped everything down with bleach of course it was diluted. I used the reptile spray and wiped the snake down when I did the enclosures then I let them soak in a bowl to hydrate afterwards.
For mites that are dead but under the scales, if you take a piece of paper and rip it off you can gently slide it under and get them from the snake, works like a charm.