From memory ..... the Bose amp cover stays where it is. The screws for the parcel shelf are at the bottom of a deep-ish recess in the Bose amp cover.
Can you get a neighbour to take photo's of you lying in the boot carrying out this job ......
Thanks Migv6 and Andy
I have now managed to carefully lift the shelf up in it's normal position and found there are no screws / bolts are anything else holding it in place. Mine is a very late miggie without the blind, and it seems they decided no heavy fixings were required. With the shelf out of the way I will, as you say Migv6, be able to get to the screws fastening the Bose cover to the body of the car, so when I install the replacement shelf with blind I will be able to screw it into position. I assume the 3 x 10mm self locking nuts are those that go on the three studs under the blind unit.
As I have been able to lift the shelf enough to see underneath, I have been able to, regrettably, see that there are no fixings for a blind, and with the moulding as it is, will not take a blind unit. Just as well I have my new shelf, as cutting any piece out for a blind I deem is not possible with this shelf design.
As for pictures of me laying in the boot Andy; no, I do not humiliate myself like that nowadays!