It has been awhile since I changed mine, but.....
on the top, behind the tweeter/ALT unit there is flat piece that if I remember correctly is somewhat flexible. Use a screwdriver to pry it up and off. Once it is off the screws that hold th ALT on will be revealed. I think there were two. Remove those and lift the ALT unit off. There will also be a connecting cord that needs to be disconnected. It just unplugs. After that it is just a matter of sliding the old grill up and off. It will be tight and something will need to be inserted carefully between the bottom of the grill and the black base of the 9 to get it started.
Beovision 7-55 with Beolab 7-4, 9s and 4000s
Beovision 10-40 with Beolab 1s and 6000s
Beosound 1, 5, 2000, and 3000
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