At the point of purchase last year, i ordered the option 719 brown seats for my carbon black (which is dark blue in reality) RTLC. Which sets it off wonderfully in my opinion. What I did not anticipate or knew at the time is that there is a 3rd piece, namely the backrest of the top box, which in my case remains black. I recently saw a proper bona fide 719 RT from birth with the correct backrest, hence i know it exists. So there must be a part number. Which I cannot find. It appears the backrest is one part along with the top box lid? Anyone here more in the know?