A prop assembly (28) has interior (30) and exterior (32) members. Each member includes a plate (34) with distal and proximal surfaces and attachment components (36) on the distal surface of the interior member. The distal surface of the interior member is adapted to be secured to a support surface. The interior member includes a cylindrical tube (40) with threads (46). The exterior member includes a cylindrical tube (52) with threads (58). The threads of the tubes are rotatable with respect to each other. In this manner the distance between the distal surfaces is adjusted.
