I don't have the time to give you pictures to go along with my description but here it is.
There are five screws holding the JB3 together, four under the rubber pads/feet and one underneath the battery door compartment directly between where both batteries are inserted. Remove all five screws, and the top cover of the jb3 should lift off fairly easy without any prying of the cover. Now there are several screws you will see on the top of the main circuit board. Two are used to attach the main board to the housing and four larger screws are used to attach the hard drive to the main board. The two smaller Phillips head screws to the bottom left and right of the display are the only ones you need to remove. Once removed, carefully lift the main board out of housing by lifting the top end of the main board, which has the firewire/usb/lineout connectors. The bottom of the main board has several flex connectors which need not be removed to exposing the rear of the mainboard. Think of it as a flip-top lid, which you open and leave on its hinges. You now have access to the optical connector which you can reseat flush to the main board and re-solder. There are two solder pads holding the optical connector on from the top, three from the bottom and three from the left side. It's important you make sure the optically jack is seating as flat on the board as possible. To do this optical job right, ideally you should use a tiny drop of liquid flux to each pad and add only a bit of solder to melt the solder which is all ready there. Do not gob it on. If you have a variable temperature soldering iron, do not set the temperature over 650 degrees, which is the high-end temperature for surface mount repairs. Excess heat for any duration of time can cause components to fail. BE FOREWARNED!!! If you have some soldering experience, it is a pretty simplistic job, as there are few components laid right near the connector and the ones that are there are relatively large. If you have second thoughts on the soldering job, don't do it. Send me A PM and I'll see if I can help.
Good luck.
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