Systems and assemblies are provided for reconfigurable waveguide (RWG) blocks having fixed waveguides therein. The RWG blocks can receive multiple self-aligned simplex ferrules to achieve customized fiber shuffles that are reconfigurable. A RWG block assembly includes the RWG block with fixed waveguides, a parallel-fiber ferrule interface to install a parallel-fiber ferrule, a plurality of simplex ferrule interfaces to install one or more simplex ferrules which allows the simplex ferrules to be positioned modularly within the RWG block assembly. The fixed waveguides allow optically coupling between the parallel-fiber ferrule and the one or more simplex ferrules via the RWG block. An assembly can also include a RWG block housing with the RWG block installed therein, and a carrier bracket coupled to the RWG block housing that receives a plurality of simplex ferrules such that each of the plurality of simplex ferrules can be positioned modularly and self-aligned within the carrier bracket.