I'm in the process as of right now to my set of JDM headlights. I am using TSX projectors, they havn't yet arrive, but I am just prepping the headlights. When you take apart the JDM headlight, you can take off the reflector and it will leave a pretty big hole behind the headlight. I believe you could place a projector behind there and make a projector holder and it will be able to be adjusted. To me, it doesn't look as difficult as it sounds, Honda-tech has a few 4th geners with retro-fits. Try searching around there, I'm sure there was a short write up on how to do this to JDM headlights, I havn't seen any for OEM headlights as of yet.
http://www.honda-tech.com/zerothread?id=1140741