  We present a procedure to extract the generalised eigenvectors of a
non-diagonalisable matrix by considering a diagonalisable perturbation of it
and computing the non-diagonalisable limit of its eigenvectors. As an example
of this process, we compute a subset of the spectrum of the eclectic spin chain
by means of the Nested Coordinate Bethe Ansatz. This allows us to show that the
Bethe Ansatz of the finitely twisted spin chain contains enough information to
reconstruct the generalised eigenvectors of the eclectic spin chain.
