There's a couple of hot pepper spray formulas on the web that take advantage of the capsasian in the peppers to repel just about anything that likes to eat rubber and soy insulation. I bought and used this stuff quite a few years ago to spray in the engine bay of my cars in winter storage because it contains a wax that coated well and suspended the repellent. Worked fine for me.
I put these all around the RV and tractor. 2 years and still all good. I see field mice all the time near by while bush hoggin. I also drop dryer sheets and kill bait. Can't ever have too much, but I think these to the most work.