The 5.4 MM lens will not focus because the lens needs more threads, it only came close to focusing when held near the treads and got softer and softer when screwed in...removing the stock lens was pretty easy...I used Isopropyl alcohol to make the large amount of glue (photo 1) /paste brittle and removed it after waiting a few minutes with a dental pick. The I used a very small needle nose vise grip with heat shrink on it to break the seal and unscrewed the lens with my fingers. At least I can now install a lens just by removing the 8 screws which holds the camera housing on and unscrewing the stock lens which I reinstalled. I want a lens with less field of view to eliminate distortion. Pic 2 shows lens removed with 2 lenses, pic 3 is close up of 5.4 lens screwed in but it can't focus like this, pic 4 shows both lenses from the back the one on the left is the stock lens and it's larger opening will allow for more light to enter than the 5.4 I was trying to install on the right.