detailed steps just for OLBA to have MEA listed
This operator is not included in GSX so, regardless of the code, it cannot appear (there's no repaint for it), the only option to have it is either wait that we'll add it, or add it yourself as an USER livery, using the PaintKit.
But DNATA is available, so you might want to start with it. If you want to add it to the whole airport, just select the topmost node, the one labeled "Airport", which means all your changes will be applied to all the selected parking (all of them, in this case ).