they are two masked screws they fit this panel
you feel them with a hook (pict 1); insert the hook between both panels
drill 2 holes (pict 2) + make the corner (in blue) smooth to avoid any sharp angle + do
not unscrew fuse box if you do not remove the panel because there is a thin plate on the other side + do not drill the red cross marked hole ( this screw has no effect on the panel )
in my case , polyurethan glue has to be destroyed with a small hook ; I feel this not an original glue ( I'm 2nd owner )
rebuilding (pict 3)
And finally as announced by Spacy, I dn't have any acces to the tap. It is masked by the black shell that protects against water leakage
