Thermal Paste life

When putting my new computer together, I applied a heatsink which had some thermal paste already applied on it, so I put it on top of my cpu and screwed it down. A while later the psu died, so I disassembled the entire computer to ship back the psu and case. Right now the heatsink and cpu are sitting in boxes, and I was wondering, will I need to wipe off and reapply the thermal paste when I reassemble to computer? This is a high-end cooler, so I assume whatever they put on at the factory is pretty supremo stuff.

If so, any good guides for doing it for processors? I've done it a few times before for xbox360 chips, but I'm not too confident in the steps I take.

like hunter sated and just about any method works for applying at as long are you remember less is more