To reattach the keyboard I found it necessary to keep the kid open and push the keyboard all the way down; otherwise, the screws didn’t engage.

I did find that, strictly speaking, you don’t need to remove the ribbons. If you carefully hold up the keyboard up towards the screen with one hand, you can remove the old RAM and install the new one with the other. I suppose you could also use a length of masking tape to hold the keyboard up.

I found it easier not to remove the ribbon, especially as I couldn’t find my plastic opening tool.