I wish I could help. I could not find a service manual for it - though that is not a surprise. Every time I think I might have lucked out, I end up back
here, with no help.
You may have to take it to a shop where someone who likes to wrestle notebook cases has done this before. I suspect, assuming you found all the hidden screws, you just need to find where the case snaps together. What I often do is insert Popsicle sticks in the cracks and work my way around the case until I find the hidden keys/latches - and of course, strategic placement of tongue is essential. Good luck.
Note too, that it in my experience, it is not a wire that comes loose where a touch of solder will fix it. Typically, it is the plastic mount the connector sits in, or the connector itself has broken. If the mount, some epoxy glue may work. Sometimes, it is the tines of the contacts that have lost tension. These can be bent back with care, but like most springs, once tension is lost, it can never be fully restored unless the metal is re-tempered.