I have this on my 1989 GL 1500. You have one part of a Hondaline Chrome Guard Set, the part that fits around the trunk. Cost for the set inearly 1990s was $156.00. My paperwork gives the application 88-90 GL 1500. The part foralong the saddlebags and across the back are in three pieces.
If anyone decides to take this I can email them the mounting instructions.