Some intercoolers have the tanks held on with epoxy, so you don't want to put gasoline or carb cleaner in those. I think filling with hot water and Dawn and letting it soak is the way to go, then rinse well. I'm also not really concerned with getting all the little droplets of water out before it goes back on the car. Just pour it out, put it on and go for a drive. Make a little boost for a few seconds, say 2-4 psi, to get it warmed up, then drive some, then make all the boost you want to dry it out. Assuming your MAF is before the turbo and not after the intercooler the water really can't hurt anything - it will be less than what is injected with alcohol or water injection under boost.