The F91 is the M8 Convertible — the G14's structure, with a twin-turbo V8, four-wheel drive and the widened M wings on top.
None of which touches the boot lid. It comes from the G14, sits over the same roof stowage and uses the same hinges. Looking for a boot lid for an M8 Convertible means looking for an 8 Series Convertible part; only the apron beneath it, with its four tailpipes, is M-specific. Boot lids are what reaches us from this car.
The reverse does not hold. There is no carbon roof on an F91 and there cannot be one — where the F92 coupé carries carbon fibre, this car carries its folded roof.
