VERDICT INDICATOR

Hi All
I have a Verdict indicator - lever type with a range of 0.5mm or so
which has stopped working.
The problem seems to be that the dial has become loose from the body of
the instrument and if I hold the two together it works OK.
I've taken the cover plate off the side and had a quick look and it
seems that the dial is held on by two screws behind the face of the
dial.
I can't see how to get it to pieces to tighten the screws - can anyone
point me in the right direction please.
Russell