Mice ***** is one of the hardest compounds to neutralize. A lot of 'fresheners' don't work on mice like they claim. If you look up Mythbusters on youtube and search for "Mice *****, Mythbusters" they did an episode where they came up with their own formula using a blend of household products which worked better than the commercial products they tested.
I tried this on my Land Rover after the mice had gotten into the heater box through the outside of the vehicle (thank's land rover for NOT putting a screen over the air inlet!!). The smell was so intense I couldn't hardly bear to drive the vehicle ...and I grew up on a farm, so I can handle smells!!! Anyway, I followed their formula to a "T" and, yes it works! In order to get at the heater box, the entire interior pretty much has to be removed including seats, front carpet, dash and so on. Plus then you have to re-do the AC/charge. It's a TON of work.
Instead, I took a 3' length of 5/8" clear tube (connected to a small shop vac) and fed it through the heater vent from the passenger's side to the main hvac chamber. Using a mini-camera/scope (also snaked into the heater box so I could see what I was doing), i managed to suck out all the mouse nest bit by bit. The hose has a somewhat arc in it which allowed me to rotate it and 'steer' it to where the next pieces were. Took a while, but I got it. I was also able to remove the blower and remove the main mouse nest material in that area. Once I had all the next material removed, I made a 180 degree spray nozzle and on a small hose and fed it into the box and sprayed the anti-***** solution all around. I mixed the solution into a bucket and used a $10 mini submersable pump I already had. It worked great! The bad water drained out the AC drain ...and I also left the vacuum tube in there to 'suck' the water out too so it wouldn't run onto the carpet. I used a brush and applied the 'anti-***** solution' in the blower fan area and anything I thought might have been in contact with the mice. I did it a couple times. Again, I was using a mini scope camera like you can get at Harbor Freight (which I already owned) so I could 'see' what I was doing inside the heater box. After I let it 'soak' for 30 minutes or so, I rinsed it down with regular water, put it all together and let it dry. The whole process took maybe 1 1/2 to 2 hrs. I also fabbed up a mouse-proof screen over the air inlet so mice can't come in again.
The short story is the mouse smell was/is gone and has never returned since, even on hot days. Not even a whiff, ...and I did this job about 5 years ago! It even smells pleasant in there as I used a little lemon scent soap in the formula like they suggested. I am keen to mice ***** smell as I work on a lot of old cars. I can smell it in an instant. So I'm please to report it works. I hope this story helps someone. But you'll have to apply it wherever the mouse ***** is. I don't know the formula off the top of my head, but do a search like I described above, you'll find it.