Does anybody know if there is a workshop diagram or manual to allow me to get to the inside of an SD7

Let me explain what has happened.

As I was moving my SD7 I knocked the rear USB socket and it has now disappeared inside the unit. I can still use the keyboard and use the file system via the USB ports on the front but obviously cannot connect it to a computer which is by far the easiest way.
I've removed all the screws from the bottom but cannot gain access to the inside and I am frightened to use too much force in case I damage it beyond repair.

Hope someone can help.

Alan