Abstract: A substrate-lead subassembly (34S), having relatively fragile lead retaining hooks (68) which project from opposite sides of the subassembly outward beyond the edges of an opening (38) in a housing (36) of a housing subassembly (32) in which the hooks are to be received, is partially assembled into the housing in an initial assembling station (80). More specifically, as the housing subassembly (32) is advanced horizontally into the initial assembling station (80) above the substrate-lead subassembly (34S), opposite sides of the housing (36) are released in sequence so that the housing subassembly drops by gravity through a series of controlled tipping and downward vertical movements to receive the lead-retaining hooks (68) on one side of the substrate-lead subassembly (34S) in the housing with outer ends (70) of the hooks in seated interlocking engagement with an inner support ledge (52) of the housing.