The fragile plastic plates that retain the Rover SD1 Parcel Shelf have a pretty short life expectancy.
I have not owned a car with an undamaged set and if they are all banjaxed the parcel shelf moves around like a demented supermarket shopping trolley when the hatch is opened.
Worse, when driving on our awful british roads the shelf bangs away like a woodpecker on heat.
This led me to design bullet-proof replacements (drawing quality - 4/10). All the work can be done with a hacksaw, a decent set of drills/files, some fine emery paper and metal polish.
When finished, fix with plated countersunk screws using spire nuts behind the shelf sides to hold them firm. It results in a durable and cosmetically good solution to this annoying little problem.
It was so successful, I made up another set to use on my (then) other car, the VDP Efi.
Click on the improved retaining plate image for enlarged version.
Regarding the annoying habit of the rear parcel shelf to bang away in it's now secured location - a couple of strips of sticky-backed foam draught excluder fixed along the bottom of the locating ledges quietens down rattling just fine.
Past experience with "Blue Peter Techniques with Sticky-Backed Stuff" are all the qualifications needed to complete the above task!
Rover SD1 Tips 'n Tricks - #4 - Parcel Shelf Retaining Plate
A Major Review of Rover SD1 V8 Electronic Ignition System
Description & Analysis Here:
Components & Testing Here
Click image to enlarge