  We perform a dedicated study of the $q \bar{q}$-initiated two-loop
electroweak-QCD Drell-Yan scattering amplitude in dimensional regularization
schemes for vanishing light quark and lepton masses. For the relative order
$\alpha$ and $\alpha_s$ one-loop Standard Model corrections, details of our
comparison to the original literature are given. The infrared pole terms of the
mixed two-loop amplitude are governed by a known generalization of the dipole
formula and we show explicitly that exactly the same two-loop polarized hard
scattering functions are obtained in both the standard 't
Hooft-Veltman-Breitenlohner-Maison $\gamma_5$ scheme and Kreimer's
anticommuting $\gamma_5$ scheme.
