I found that a stiff bristle brush and a shop vac work well for getting the dirt out of the inside of the cab, wear a dust mask and scrub around with the brush DRY while holding the shop vac hose near where you are brushing.

If you have any odors like mildew or smoke, try Zorbx , it was recommended to me in another thread and since then my wife no longer buys Febreze. It works really good, has no smell and removes odors almost instantly.

Sorry, yes, I only spray a dusting of it inside the cab and wait for it to dry, take a whiff, repeat as necessary.

I haven't bought alot of EM's, but I just got in there with a new soft paintbrush, I taped it to the end of the shop vac hose and gently brushed off the bottom board components to remove as much grime as I could. I cleaned the parts of the plywood I had access to and called it a day. If you are doing a full restoration them maybe you would go to more extremes but for me I just like to clean them up and play them.

Make sure to empty your shop vac before starting so you can retrieve anything you suck up by accident and watch out for loose labels.