Checking / adjusting fork oil level

This may be a dumb question, but is it possible to measure / adjust the fork oil level without taking the forks off the bike ??

You can add or subtract from the oil level like that, but knowing the actual oil level going by the book requires removing the spring, bottoming the fork, completely flooding the fork with excess oil, bleeding out any trapped air, and then removing the excess oil in order to drop the oil level down to where you want it.

I've found that setting the oil level by the book, putting the forks back on the bike, riding the bike, and then simply re-measuring the oil level will get you a different oil level reading.

Thanks for the reply - I guess I figured that but was hoping I was wrong !!