A thermal management system/method allowing efficient electrical/thermal attachment of heat sourcing PCBs to heat sinking PCBs using reflow/wave/hand soldering is disclosed. The disclosed system/method may incorporate a combination of support pins, spacer pads, and/or contact paste that mechanically attaches a heat sourcing PCB (and its associated components) to a heat sinking PCB such that thermal conductivity between the two PCBs can be optimized while simultaneously allowing controlled electrical conductivity between the two PCBs. Controlled electrical isolation between the two PCBs is provided for using spacer pads that may also be thermally conductive. Contact paste incorporated in some embodiments permits enhanced conductivity paths between the heat sourcing PCB, a thermally conductive plate mounted over the heat sourcing PCB, and the heat sinking PCB. The use of self-centering support pins incorporating out-gassing vents in some embodiments allows reflow/wave/hand soldering as desired.