Dead smell in car coming from cabin filter area

Hi all.
Need some help here instead of paying a fortune at the dealer. Over the last few days, there has been a putrid odor in my car. I pulled the cabin filter inside glove compartment & saw mice droppings in the cleats of the filter & the smell is definately down that area.
Looked around the engine & nothing but now I guess I need to start disassembling pieces under the hood. Would anyone be able to assist me with this? If smell is coming from where cabin filter is, what would you do for next steps?

 

The "smell" could be anywhere in the duct work for the cabin fresh air.

Start under the hood and work your way to the vents in the cab. Most likely in the cowl area, since the filter had not been chewed thru and the droppings were in the pleats.

 

Good luck getting rid of the smell once you find that bastage. Had one get ground up in an old truck of mine back in college. HOT summer day and I cranked up the ac on my way to school. After class I smelled something musty. Next day it smelled like death. 2 months later that truck was gone and was stuck riding my bike or motorcycle for the semester.

Seriously good luck man. I'm gagging even thinking about that putrid smell.

 

Mouse poo in cabin air filter