I too just finished a kegerator. One of my faucets had a small leak. So, I decided to follow Perlick's directions like I should have from the start. Prior to using the faucet, Perlick recommends taking their faucet apart, soaking everything in beer line cleaner, rinsing then putting everything back together.
Much to my surprise, the leaky faucet had a bearing cup installed upside down which, when installed properly, fixed the leak. Consider taking the faucet apart to make sure everything is installed correctly.