I also help taking the cowls off (top and bottom), and at the same time look
for loose wires, cables, leaks, etc, since I have to fly to the mechanic,
which also warms up the oil.

Part of it is that I have more confidence taking things apart than putting
them back together correctly. (My mechanical Nikon's light meter broke once,
so I took it apart to look and see inside. There are a lot of small parts
inside a camera. I brought it to the repair guy and said I had done half of
his job for him, but that I only had four screws left over at the end)

The same approach on a plane might have a little different outcome, so I'm a
little hesitant to start taking things apart, even though the oil change,
plugs, etc are pretty simple jobs.