longitude bar installation

Does anyone here installed the Longitude bars on the Tonale? I just received them but there was no instruction added. I have to remove the metal bar across the roof but I'm not sure if this is screwed on or just clicked in place and I can pry them out with wedges?

The bars themself come with 4 screwholes and 4 plates to hide the screws from the top so that would mean in my eyes that the longitude bars are screwed from the top. However the stock metal plate does not have these screw holes on the top?

Anyone here that has these removed themselves?