... squirrels are glorified rats with nice jacket. They are rodents and can chew even through the shingles and plywood to get inside. Let the nature take it course or you will face infestation very soon with all the ramifications - diseases, damages, destroyed vegetation, wires etc. Overpopulation of squires will attract various predators and then you will be screaming bloody murder all because of your own stupidity.

After having to repair the "chewed off" wiring in my truck multiple times, I have no love for squirrel nests under hoods. They love to chew them down to the nub so you have nothing to attach to.