A disk drive having a novel head-gimbal assembly (HGA) which is attached to an actuator arm of an actuator assembly. The HGA includes a read/write head, a flexure, and a suspension arm. The suspension arm has a first end including the flexure supporting the read/write head, and a second end including a hole having an attached swaging member extending through it. The swaging member includes a baseplate and a swaging boss which interface at an annulus region. A circular hole is formed through a top surface of the baseplate and extends downward partially through the swaging member. A non-circular hole, concentric with the circular hole, is formed through a bottom surface of the swaging boss, and extends upward partially through the swaging member. The non-circular hole has a smaller diameter than the circular hole. The shape of the non-circular hole may be any geometric shape such as a two-lobbed swaging hole, a three-lobbed swaging hole, an elliptical hole or a hexagonal hole. The swage boss of the swaging member is inserted into an opening in the actuator arm. A compatible non-circular key, which is a rod of the same configuration and size as the non-circular hole, is inserted through the hole and non-circular hole in the swaging member. The non-circular key is held at both ends by a fixture and turned so that the non-circular hole is deformed. The swage boss expands in size to form a tight interference fit with the actuator arm. The plastic deformation of the swaging member is located at an interface region between the baseplate and the swaging boss. Since the plastic deformation is confined to the interface region, any formation of kinematic deflections on the HGA due to the mounting process is eliminated.