There really isn't much to say about this modification. The NetGear MA101 is a USB 802.11b Wireless NIC which comes with a small moveable antenna. There are in fact two antennas, the other is a track on the PCB and a diversity switch selects between the two.
The MA101 moveable antenna is simply soldered directly to a space for an SMA socket on the PCB and since the connection to the socket is already being used, there are no fiddly surface mount components to deal with on this one!
Opening the case is simply enough. Holding the unit with the base facing you and the USB socket at the bottom, use a sharp knife to remove the 3 rubber feet. Start at the lower left and work clockwise, the fourth rubber foot does not have to be removed.
Under the feet are the screws holding the case together, remove them and carefully open the case. The rear of the unit is also held together with plastic clips so lift up the front by the LED's and slowly work the lid off.
Not much else to do really other than unsolder the coax for the supplied antenna and solder a suitable socket of your choice. I used a PCB mount SMA socket. Drill a hole in the lid for the socket and that's it!
I bought my PCB Sockets from RS Components (http://www.rs-components.com), part number 111-712.