[MuskyHunter]

I have in my past vehicles made a funnel out of whatever material is convenient, and put the narrow end on the air inlet. I would then turn the fan on and go back outside to spray Lysol disinfectant. Just be careful and take precautions so that it doesn't come in contact with seats or console plastic.

I had to go through a series of these treatments on my 240sx. To make a long story short, the dashboard shook, the car started to reek, then taking out the blower fan to find a dead mouse that went through centrifugal torture. Lysol did it's job.