I removed the cowl and looked for fresh air intake there, could only find two holes on bottom of each side, drivers and passenger. These holes consisted of an oblong opening and round opening, installed 1/4 steel mesh over them. These holes did not seem to lead anywhere internal though. These is a gap around edges of cowl that are normal, no covers for them.
Always have installed mouse traps in car, rather have dead mice than live ones ruining car.
Will keep looking