I've had to deal with mites a few times, so far they weren't terribly hard to get rid of. My procedure is as follows...
Toss substrate and soak hides and other cage furniture in scalding hot soapy water for at least an hour, completely submerged. Do the same with the tank or tub and scrub the hell out of it.
Spray snake down with reptile relief spray and allow the snake to remain wet for at least 15min.
Set up clean cage with hide, water bowl, and paper towel substrate and add snake.
Treat snake and repeat cleaning for tank and furniture once a week for a month.
So far this has worked for me.