Mike, 1. Have you ever visited a tomato cannery? There are several in California to choose from: woodland, Stockton, Modesto, etc. Very messy, but interesting Process from Harvest to Store Shelf. 2. Have you ever changed out an engine on an aircraft - old warbird radial engines are pretty messy and make good video. Go to the Air Museum in Tillamook Oregon (visit the cheese factory while you are there - that's pretty disgusting) and see how they maintain the aircraft. Or go to the Warbird collection in Chino, CA - Or find any cropduster. Of course cropdusting is messy too, after you show the audience how to fill a running aircraft with pesticide, fertilizer or seed, you can show how is applied to crops.
3. Find the largest open pit excavator in Germany - built by Krupp - it is enormous and removes over 100,000 dump trucks of material a day. The maintenance alone on that must be messy!
