actually tried this setup following ur steps n have found the following
befor installing the camera u need to remove the led ring of bulbs by unscrewing the lens cover n simply cutting them off
the lens needs to be a 16mm cheap one from ebay for about £5 n simply undo the grub screws n unscrew the lens n replace with a 12mm thread 16mm lens
also when u have the lens removed ther is a piece of glass inside the camera that needs to be removed right in the bottom with a small screw driver, it helps the camera pick up the ir
this setup is good for about 25 yds, anymore you will