eLiu - can you think of a way to reach the top of the CPU without removing the HSF once it's installed? I think that answers your last question. Unless you have really tiny hands, a hair-strand thin mirror and can refract light, I think you're removing the HSF to remedy the problem. Not picking on you, just relieving some tension from a WONDERFUL day at work...and my highly aggrivated pulled groin...anyway...
As for a permanent solution, I got the Conductive Pen. It was about $12 when I purchased it. Not that expensive considering what you're doing. If you've ever done any soldering, this shouldn't be hard. Not that hard even if you have not. Find a needle or something similar to apply it with....works like a charm.
As for how to apply it, I got a piece of styrofoam and stuck my processor in that to hold it while I connected the bridges. I do not recommend putting it in the socket, but to each his own. I wouldn't feel comfortable with my hands in my case trying to put that stuff on, but if you pencil it, I guess it probably doesn't make that much of a difference.