When you apply thermal paste, you DO NOT spread it out with anything. You are supposed to put a small dab (about the size of an uncooked grain of rice) in the center of the CPU core, then the force of the heatsink being attached to the socket will spread for you. Too much thermal paste is a bad thing, as it can greatly reduce its effectiveness and most cheaper pastes are conductive, so its not too good to get that on the CPU packaging, as the bartons do have circuitry on top of the package around the core.