There's a spray that I use called restorzeit sold by NAPA it's like armour all. Spray I intire engine , rubber, compartment, wires. It has a funny smell and next year what ever you spray will be real shiney. I tried mothballs,drier sheets, peppermint etc. I know it works I have a bull dozer left outside and spry under dash board, wires,hoses etc. and have no mice damage prior to this my dozer would be damaged. The product is made by Korkay co. It smells good to us but bad to them little pieces of €€€€€€. Look up restorz tire and viynal treatment.