I also tried the same kinda DIY some time back (I guess in the first month of ownership back in August). The thing with cloth and sponge is that they retain moisture for looooooong.. and I really mean loooooong!! After you give your bike a wash (which I do on a weekly basis), the visor starts to fog. This is also harmful for the metal parts inside the assembly (bolts and clamps) and the prolonged moisture can hamper the internal circuit too. Also, and above all, the cloth and sponge would start to decay over some time leading to foul smell

So, at the end of it, I bought some rubber gourmets from a hardware shop and installed them for all the bolts that I can see in the head lamp assembly and that worked for me.