So today I had some time to prepare the boat for the install. I removed the rear sundeck as well as all the stuff around the engine to have access to where the pumps should be mounted.
Firstly I planned to mount the pumps above the silent master horizontally. I therefore let build two supports made from aluminum to be mounted at the transom where the pumps are mounted originally. As the transom is not a flat surface and as the mounting points laminated to the transom are not levelled out (it looks as a the guy who laminated was drunk) it would not turn out as I planned. Picture shows the two supports but not the tray where the pumps would be mounted to.