This has nothing to do with an extractor but is about draining your oil.
11% or about 600ml of your oil sits in the front sump that collects the run off from the timing chain/gears, it has it's own pickup tube that sends the oil to the main sump.
The oil in the front sump doesn't drain when you change the oil but gets diluted into the 5-6 litres of fresh oil and every oil change is like that.
I got it in my head that I wanted to drain that oil each time so while I had the oil pan off for the rebuild I located the thickest part of the cast aluminum wall in that front sump, drilled, tapped and installed a removable drain plug.
The wall in that location is 10mm thick so lots of meat there for threads.
Is it necessary? Absolutely not but I can fool myself into thinking my oil analysis is 11% more accurate
