Dave,
With an un-fused supply, you are basically at the mercy of the Secondary side of the Transformer feeding the Installation.
Considering the lack of fusing, I would get Cover-up gear around the main, depending upon what you were doing.
Other way you could do it is with Insulated Gloves and Protectors and Isolate your Phases by Insulating them with the Main Switch turned off and then remove them and Insulate them.
Other side of the coin too, wear a face shield, in case something does go wrong.
