Depending on the condition of the truck, I have taken out all the seats, carpets and clean the cab corners out and have actually pressure washed the cabs out. Wash with bleach water after that. I try to not handle as much of that crap as possible. When it drys, I use some odor remover from Kameapart or WallyWorld and spray down everything. The seats I will wipe down and bang around to get as much dust, crap, etc out of it. Usually the seats are crap anyway, so I don't worry about ruining them. I spray the seats a couple of times with the same odor stuff. It usually does the trick. I use Irish Spring to store them.

One place the mice get is in the headliner above the windshield. Usaully it ends up rotting the metal above the windshield from the mouse urine. That is a hard place to clean out.