  A certain U(1) model in 2 dimensions, describing four right handed unit
charged Weyl fermions interacting with one doubly charged left handed Weyl
fermion, is exactly soluble and has massless Majorana-Weyl composites.
Instanton induced fermion number violation is essential for 't Hooft anomaly
consistency. The associated 't Hooft vertex can be analytically computed in the
continuum, including finite size corrections. This number is reproduced in a
dynamical simulation employing the overlap.
