Thanks for the warm Welcome!
I hope we will have some hot run together in the future!
And thank you as well to showed me where it was, I searched for 30 minutes yesterday night without even looking there.
At first I though it would be impossible to fill it up without removing the wing but in fact it is quite easy!
From the front it is easier:

Just turn it like a normal cap:

And more than enough place to put a funnel:
