Had the Taco in to get all weather tires this morning, and our mechanic found more rat nesting material on our engine. (I thought Shelly had been cleaning it out every morning before work--nope)
So I stopped by our hardware store and bought one of these:

It's a flashing yellow LED, which evidently the pack rats around here don't like. The guy at the hardware store said it will work, but only if we wash the engine with degreaser to get rid of the smell of previous rats. It was up to nearly 50 degrees, and may not be again for awhile, so we immediately took the Taco to the car wash, only to find he doesn't have degreaser. So Shelly gave it a power wash, to my consternation, as I was afraid water might get in the air intake. But, the engine started, so I guess we're okay there. Not sure water is enough to get rid of the rat smell.
I'll report on how well it works. We get our money back if it doesn't (if we follow directions, which means using degreaser if we have to).
Also bought one of these

which I have more faith in. Right now it's in the cab of the truck, to see if we have any customers there. We may try it under the truck, though I'm afraid we'll attract rodents who wouldn't otherwise bother us. Then, there is the Jeep, the porch, and workshop. Plenty of good spots to try. I think this one may only work on rats, (the Rid-a-Rat claims to work on mice too) but the mint and Irish Spring do seem to keep our mice away.
Tom