Speaking as a former ground crew, most, if not all stenciling on aircraft are for the benefit of the Aircrew. If the aircraft had to be "turned round" by them (only likely if they landed at a different, non type operating airbase). The information given on the stenciling would tell them the pressure/type of lubricant etc, needed to replenish the aircraft. Failing that they would ring the home base and ask the engineers advice on what size spanner/screwdriver was required and then ask the ground crew to bring said tools and while they are there "could you please turn the aircraft round as you will be far quicker and we can get back to base".
Why have a dog and bark yourself
Great work btw.