Well done. Ive been wanting to try this on my N900 for a while.

Ive been shooting IR on an old sony H9 for a couple years now. Recently tried modifying a cheap little micro cam and was successful. I didnt have any old film so used a floppy disk as a permanent IR pass filter. Still getting some visible light through. But was just an experiment to see how easy it was to remove the hot filter out of the camera module.

What plastic did you use to replace the hot filter ?

Are you using anything as a IR pass filter ?

If I had the time, money, design and craft skills. I would make a new back cover with rotating lens cover. That could switch between "off/covered" for when not shooting, "hot filter" for shooting normaly and "IR pass filter" for shooting IR.