It seems easiest to just remove this screw now. It comes out in Step 12 anyway. This way you don't have to mess with the rubber grommet.
This is where I got in trouble too. No problems on the first of my Minis, but this time one of these sockets had poor soldering and just came off the board. Basically no solder connection to the posts that are there to hold the socket in place. I ended up using a pin to pry the rest of them off, in case the others were also poorly connected. The outside of the socket is U shaped, with 2 small tabs at the lower end of the U. I inserted a pin next to these tabs and it let me lever the connectors out easily. Now I get to practice my soldering!