<OpenGeoSysProjectDiff base_file="../1d_decay_chain_GIA.prj">
  <remove sel="/*/linear_solvers/linear_solver/eigen" />
  <add sel="/*/linear_solvers/linear_solver">
    <eigen>
      <solver_type>SparseLU</solver_type>
    </eigen>
  </add>
</OpenGeoSysProjectDiff>