Furry friend keeps nesting under car hoods

We live in the mountainous desert of Colorado. We do not currently have indoor parking (will be a year before we have funds to build this). When our cars are outside without being driven for > a couple days, these guys (I think packrats based on appearance?) make nests. They haven't chewed through wiring yet but I'd like to prevent this.

The internet tells me to use peppermint oil under the hood. My husband ABHORS the smell of peppermint. Any alternative solutions, pending indoor parking options?