Parts such as the Rear Case: Oil Seal,27x34x5, Bolt,flange 8x45, Strainer Body,sca, Tube,breather are included in the Gl1500a Goldwing Aspencade 1991 (m) Australia / Kph Rear Case parts fiche.
In this schematic the "Bolt,flange 8x45" is used most often.
The sub assemblies and components that make up this Rear Case include this Case Comp,rear, the most expensive part.