This is right up my alley, but you're right, a little different. Our maintenence schedules are routine; but I am otherwise building ways of tracking this information.
So: Some questions:
1) How much customization time do you want to spend in method? I can think of a few different ways to go about what you need of varying complexity.
2) Is the person who is putting the info into excel the same person who is putting the info into excel the same person who will be putting it into method?
3) Strange sounding question: But, how is whomever is recording the actual running hours? Sounds like it's on a clipboard and a piece of paper. Are you guys running around with tablets yet? Or is/are there computer stations available?