[Reelman]

I presume that to remove the handle you are trying to separate the case? By gently trying to prise around the split of the case you should find a more resistant part that can be further investigated for hidden screws.
However sometimes a thin piece of felt is glued to one half of the case to deaden vibration where it meets the other half. Over the years the glue migrates through the felt until it effectively glues the case together. A little heat may help to soften the glue and then have the courage to force it!
Good luck with it.
Peter