Im my youth I worked as a labourer for a stucco outfit. On new homes, the meter base would already be installed - hopefully with a chunk or tar-paper or Tyvek behind it. We'd put J-bead on around the meter base, vapour-barrier & mesh, stucco, and then fill the <1/16" gap with caulk afterwards. Nobody ever moved a meterbase for us to stucco behind.
Perhaps see what they do on new stuccoed homes in your area.
