I think it depends on the temperament of your little one. You could tell him ahead of time that the "paci fairy" comes to take paci's from big kids and give them to little babies (it helps if he has a new cousin or someone in the neighborhood has a new baby). And you can have him draw a picture and put it with the pacis in an envelope and put it in the mail.
Or you could just "lose" it :) That's what we did with our 20 month old. We went to grandma's house for the weekend and when we came back we said that we forgot it there. She wasn't happy, but I knew if we announced it ahead of time. Everytime she asked for it, we said "Oh, we left it at Ya-Ya's house, remember?" and she would say "yeah" (sadly, though).
STAY STRONG. Sleep will NOT be good at first, nor will going down to bed, and it will be SO SO easy to just hand the paci back to him. A few times I almost caved. If you're serious about this, just throw them all out so that's not a chance. His sleep will adjust (and not in 2 days, it may take 2 weeks) and he won't ask for it anymore.
I almost caved one day and posted on a message board as my daughter was crying upstairs and one mom said "don't cave! We caved twice and of the three times we tried to take the paci away, it got progressively harder" So draw up support and commit.
Good luck!!