I have purchased his omega today which is great and in need of a bit of tlc and it is not working so I need to open it up. Can anyone let me know which model this is and roughly when made and which is the best way to open without having the 106 tool that it states on the back. Thanks

 

Requiring tool 106 means it is a front loading movement. I have not opened this model but I think you need to remove the crystal with tool 106 or a generic crystal lift. Remove the crown. That will have a split stem. Then you rotate a retaining ring to remove the movement. The inside of the case will have a reference number that you can use to gain more information on the Vintage Omega database.