Panel installation system and method

In certain embodiments, a panel installation method includes attaching first and second support anchors to a substrate, with the second support anchor spaced apart from the first support anchor. Each support anchor is elongated and includes a base for attaching to the substrate and respective projections extending outwardly from the bases. A tab extends upwardly from the first support anchor's projection, and a prong extends from the second support anchor's base. The method includes mounting a panel having first and second ends to the substrate via the first and second support anchors, including coupling the first end to the first support anchor, coupling an interlocking bracket to the second end, and coupling the second end to the second support anchor by engaging the interlocking bracket with the prong. The method includes positioning a stabilizing insert in a gap between the interlocking bracket and the projection of the second support anchor.