Good on you--that's a huge task, but you did it!!
The bugs on his face won't have anywhere to go without getting poisoned, so hopefully they'll die off soon. You can try to brush off and smush as many as you see if he lets you get that close. But definitely don't dip or dunk his head. That would be very bad for a chicken.
Dipping should arrest the situation pretty well, but don't get too discouraged if it takes a few days for things to go away. And of course re-treat nesting boxes and roosts.
The first month we dealt with mites was the worst. It was like we had to wrestle the chickenyard back from the parasites, and nothing seemed to work. Until we finally reached a tipping point where enough of the bugs had been eradicated or weakened that they couldn't make another comeback.
The Elector PSP is a ridiculous price, and if permethrin had touched our mites at all, I would've started with a permethrin dip instead of investing in the Elector. However, I don't regret that investment for a moment, because it was what finally tipped the scale and ended Mitesplosion 2020.
The powder is not expensive and definitely worth grabbing. Continued good luck.
