  We extract the Weyl scalars $\Psi_0$ and $\Psi_4$ in the quasi-Kinnersley
tetrad by finding initially the (gauge--, tetrad--, and
background--independent) transverse quasi-Kinnersley frame. This step still
leaves two undetermined degrees of freedom: the ratio $|\Psi_0|/|\Psi_4|$, and
one of the phases (the product $|\Psi_0|\cdot |\Psi_4|$ and the {\em sum} of
the phases are determined by the so-called BB radiation scalar). The residual
symmetry ("spin/boost") can be removed by gauge fixing of spin coefficients in
two steps: First, we break the boost symmetry by requiring that $\rho$
corresponds to a global constant mass parameter that equals the ADM mass (or,
equivalently in perturbation theory, that $\rho$ or $\mu$ equal their values in
the no-radiation limits), thus determining the two moduli of the Weyl scalars
$|\Psi_0|, |\Psi_4|$, while leaving their phases as yet undetermined. Second,
we break the spin symmetry by requiring that the ratio $\pi/\tau$ gives the
expected polarization state for the gravitational waves, thus determining the
phases. Our method of gauge fixing--specifically its second step--is
appropriate for cases for which the Weyl curvature is purely electric. Applying
this method to Misner and Brill--Lindquist data, we explicitly find the Weyl
scalars $\Psi_0$ and $\Psi_4$ perturbatively in the quasi-Kinnersley tetrad.
