I Installed these projectors myself using long screws and nuts - forgot to take pic from back side but room for adjustments were left at the back side using screws and nuts - Before installing these, you have to be sure that the light you are installing the projectors in may be totally wasted and you might have to buy a new one - In my case it costs about 500rs so yah I could try it out and risk the process.
and the real problem is not buying the projector lens, rather the HID kit - it's d2s bulb and only HID is available for D2S which costs about 7-8k from bilal gunj and keiworks is also selling one for 8k - No Chinese kits for d2s available. I am using H4 bulb at the moment which is why the light Is really poor at the moment because it doesn't fit in properly - very soon IA, I will get my hands on d2s kit and will share pics.