Parts such as the Frame Cover (gs750r: Spacer (6.8x10x10), Screw (6x20), Cushion,frame Cover, Spacer (6.8x10x10) are included in the Gs750b 1977 (b) Usa (e03) Frame Cover (gs750r parts fiche.
This FRAME COVER (GS750R assembly utilises two Cushion,frame Cover(s) - the highest specified component.