A multi-purpose pinless attachment system includes a first structure having oppositely facing recesses separated by a web region. Pairs of recesses form pivot bar bearing surfaces, and a transverse pivot axis passes through the web region at a midpoint between these pairs of bearing surfaces. A second structure defines an interior pivot channel between its distal tip and a proximal shank. The tip is separated from the shank by a gap to allow the web region of the first structure to pass through the gap while the interior pivot channel is brought into bearing registration with the pivot bar. The pivot channel receives the portion of the web region separating the first and second recesses. Surface portions of the pivot channel frictionally engage at least a portion of a pivot bar bearing surface while the second structure is pivoted relative to the first structure about the transverse pivot axis.