Self-assembly of submicron nonspherical particles into colloidal crystal structures offers a rapid process for creating complex spatially periodic templates for nano-fabrication, micro-lens arrays and photonic crystals. In particular, theoretical calculations have shown that photonic bandgap structures with non-spherical shaped bases promote defect resilient properties and wide bandgaps at lower refractive index contrasts. This makes a wider range of material chemistries appropriate for fabrication as compared to the simple inverted face-centered cubic structures from close-packed spheres. The realization of such complex structures in three-dimensions has remained challenging. In the present work, polystyrene dimer-shaped colloids with systematically tuned particle morphology― degree of fusion (DOF) between dimer lobes and degree of asymmetry between lobe radii― were assembled into 3D colloidal crystals via controlled drying on silicon substrates. The crystal structures were determined from scanning electron microscopy images on sections prepared using focused ion-beam milling (FIB). Optical laser diffraction was performed to enable structure-optical property correlations. Highly fused particles, i.e., DOF below 0.37, produced rotator structures (plastic crystals characterized by positional order and orientational randomness), while particles with a low degree of fusion between lobes resulted in true crystalline structures. Both observations were consistent with theoretical calculations and simulations in the literature. The diffraction properties of the structures were modeled using the optical Bragg equation. Additionally, inverted germanium (physical vapor deposition, PVD) and alumina (atomic layer deposition, ALD) structures from the complex templates were demonstrated.