This is a big issue for me with farm equipment - wiring is wiring, right?
Here is a good link:
https://www.hagerty.com/media/maintenance-and-tech/tips-to-keep-mice-out-of-stored-cars/
For me, knowing where to put the dryer sheets has been key: Air intake, , exhaust, over the air filter, etc.
There are a lot of "sonic solutions" but I have no direct experience. If you go sonic, let me know how that works!
One more:
https://www.wilsonauto.com/wilson-auto-blog/10-tips-to-keep-mice-out-of-your-classic-car-during-winter-storage/