Arctic Silver 5 is not electrically conductive, so in theory there should be no damage (The site still recommends to avoid contact to pins and such). http://www.arcticsilver.com/as5.htm
Note: This is just my opinion on how to do it, I may be wrong here.
But you are going to want to clean it off. Biggest problem I can see is if the paste get inside the socket, it will be hard to clean it out without damaging the pins in there. So grab some isopropyl alcohol (or an actual thermal paste cleaning solution) or sufficiently strong alcohol cleaning fluid (I'v used White Spirits before).
Wet some toilet paper or a tissue with it and clean up as much as you can, take off the retention bracket so you can get to the overflowed bits. Once its all clear, take the CPU out and see if there's any inside the socket.
If no, Perfect.
If yes, you have a problem.
Don't know of any method for cleaning paste out of the socket, but I imagine if you wet a tissue with the alcohol and hold it against the socket only applying light pressure, the alcohol will hopefully dissolve the paste and absorb into the tissue. Hold the motherboard so you are pushing it up into the socket and the paste will absorb down into the tissue.
Dont forget to give the CPU a once over with a micro-fiber pad (if you have one) and alcohol, also clean the heatsink of any paste as well. Observe proper grounding as well, don't want to zap your freshly cleaned CPU.
Edit: Leave the CPU and socket a while to dry, the isopropyl should just evaporate to the air.
AS5 certainly DOES conduct electricity! That is a sly marketing lie AS uses, where they say it wont conduct if applied properly just like all thermal paste. All silver based thermal paste will, in fact, conduct electricity. This is because they have small particles of silver and copper in the paste, as small as the minerals in drinking water which also conducts electricity. The only thermal pastes on the market that are not electrically conductive are the non-metal types such as Arctic Cooling MX-2,3,4,OCZ Freeze, Tuniq TX-2,4, or Noctua NT-H1 .
With Artic Silver 5 i suggest using a minimum of it as stated above it conducts electricity. I only put 2-3 small drops on a processor which can keep it anywhere from 19c-30c depending how much overall heat the processor generates and how well the heatsink/fan is. Some people will argue on the method or how much to put on but in my experience a little is enough as the thermal paste is just a bridge from the processor to the heat sink & helps fill the gaps on the imperfections on the processor/heat sink. Just remember to keep an eye on your CPU temps as you should check on the regular basis anyway.