  In these proceedings we present an exact distillation setup with stabilised
Wilson fermions at the SU(3) flavour symmetric point utilising the flexibility
of the Grid and Hadrons software libraries. This work is a stepping stone
towards a non-perturbative investigation of hadronic D-decays, for which one
needs to control the multi-hadron final states. As a first step we study
two-to-two s-wave scattering of pseudoscalar mesons. In particular we examine
the reliability of the extraction of finite-volume energies as a function of
the number of eigenvectors of the gauge-covariant Laplacian entering our
distillation setup.
