If the lever turns too far before the shoes, which should not be worn down too far, touch the drum, and the cable is clamped correctly, one can insert two equal thickness spacers with turned up ends, over both the shoe to cam faces.
Discs need assembling so they run true to the calliper and of course in line. I've turned up some thin Ali discs to locate & stop the spacer collar from slipping radially off-centre i.e. sideways a fraction, when the three long bolts securing it tighten it onto its seating on the plastic hub.
