how can I open an old Gould 1425 scope
 

Hi everybody,
I have an old Gould DSO 20MHz 1425 scope maybe 20 years old.
Channel 1 doesn't work anymore due possibly to an overvoltage.
I would like to repair it and see if I can change the parts on the
input stage. However after removing the box surrounding the scope I
can't remove the front panel. To tell the truth I don't even
understand how it was mounted ; everything seems to be tied or
soldered together and I can't have access to the input stage which
seems to be mounted into a shielded box behind the front panel. I
thought I have some experience on this sort of things but in fact I'm
completely stuck! Thanks for any help!
val