One embodiment of the present computer network device comprises a subassembly. The subassembly includes a support plate, a standoff extending from the support plate, a printed circuit board (PCB) secured to the standoff, an electromechanical connector secured to the PCB, an electromagnetic interference (EMI) cage secured to the PCB, and an EMI gasket engaging the EMI cage. The computer network device further comprises a guiding and retaining member that engages the support plate and assists in securing the subassembly within an enclosure. In a method of assembling the computer network device, the subassembly is first assembled before the subassembly is secured within an enclosure. Relative motion of the PCB and the standoffs is thus eliminated during the assembly process.