Mice in my Tundra

Question is there a way mice can get into the cowl from the underside other than the engine bay or only through the vents on top. 2015 Tundra

 

When you open the front doors all the way you can see rubber flaps blocking off access to behind the front fenders and cowl area. I clean behind these a few times a year because dirt and leaves get pulled down into there from the cowl area.
So to answer your actual question, yes I think there's access from underneath

 

https://www.tundras.com/threads/how-to-deal-with-mice-in-engine-bay.143884/unread
Some good info here

 

Good information in this thread on adding some prevention methods

https://www.tundras.com/threads/mouse-rodent-proofing-stage-one.44679/