I got an old PowerBook 170 AC adapter for repair. Model: M5140 (APS-20U). It is completely dead and I can see some very light plastic deformation from heat in the top right side, so it must have been working hot for some time before it died.

At first I hoped that it is screwed together, but sadly it looks like it isn't.

I want to get it open and see what is wrong, but I want to be as much as non-invasive as possible, so if I could repair it, I would be able to put it together and it won't look mangled.

Any ideas of how to proceed?