  We apply a generic formalism of light propagation to linearly perturbed
spherically symmetric dust models including a cosmological constant. For a
comoving observer on the central worldline, we derive the equation of geodesic
deviation and perform a suitable spherical harmonic decomposition. This allows
to map the abstract gauge-invariant perturbation variables to well-known
quantities from weak gravitational lensing like convergence or cosmic shear.
The resulting set of differential equations can effectively be solved by a
Green's function approach leading to line-of-sight integrals sourced by the
perturbation variables on the backward lightcone. The resulting spherical
harmonic coefficients of the lensing observables are presented and the shear
field is decomposed into its E- and B-modes. Results of this work are an
essential tool to add information from linear structure formation to the
analysis of spherically symmetric dust models with the purpose of testing the
Copernican Principle with multiple cosmological probes.
