I've got a couple of IBM 3151 terminals that are getting dim and out
of focus. I want to open the case to see if there are any internal
brightness/focus pots that can be adjusted. (I am aware that internal
voltages can be hazardous and will take precautions.) However, I
can't figure out how to get the case back off as there are no screws.
Can anyone give me instructions?

Thanks,
Dan