First, I took apart an old Logitech webcam that I had lying around. I took off the plastic casing and found the lens connected to the board. This is what it looked like:
After removing the lens from the board, the filter sat on the back. The lens could be unscrewed from the filter holder, so I removed that as well, being careful not to smudge the lens. Lo and behold, inside the filter holder behind the lens was the visible spectrum filter. I tried removing with a razor blade, but it did not budge, so I used the old brute force method and smashed it out.
More after the break
Then, I needed to replace that filter with the IR filter. I had acquired some exposed negatives by placing an ad on Craigslist and going on somewhat of an adventure to retrieve them. Finally, after getting them, I cut them up, layered two on top of each other and taped them onto the back of the filter holder. I had to be careful not to cover the image area with the tape. Here are some pictures of the film negative.\
Finally, I put the camera back together and tested it out. Here is an image of camera put together without the plastic. As you can see, the tape sticks out, but makes no difference.