A prototypical frustrated magnet in which structural disorder plays a key role is SrCr9pGa12−9pO19 (SCGO). It is postulated that structurally ordered SCGO hosts a spin-liquid ground state, however it is not possible to prepare this composition with p<0.98 being the limiting composition. We have recently shown it is possible to change the nature of the structural disorder in SCGO by partially replacing Ga3+ with the larger non-magnetic ion Sc3+. Our preliminary results show that Sc-substitution has a dramatic effect on both the distribution of the Cr3+ and the magnetic susceptibility. We propose to study the diffuse scattering to investigate the role of structural disorder and magnetism in SCGO and Sc-substituted SCGO in order to to correlate the differences in magnetic diffuse scattering across the range of sample compositions with the differences in structural disorder.