I just love machinery (of all types). I can't think of any specific examples for you, but try the following:
Capture the "essence" of the machine. If it is a huge scraper, get down low, and use wide angle to emphasize the wheels, or bowl, or engine as being powerful, and huge. You don't need to get the entire machine, but get enough of it to show its "character".
Details, such as above, might benefit from just a little more context; (show where it is in relation to the bowl, for instance). Show other details, such as the operator's position, some controls, details of engines, wheels, tracks, implements, etc.
Since they're not using them daily, you might have to concentrate on details until next spring.