I had mine taken out by the dealer because I needed to replace one of the moveable pieces that keep the cup in place. Basically you have to take apart most of the tunnel. BTW, when they took it apart they found a mouse nest. Gross!
I have a carbon cupholder that i would like to DIY. 3POINT8 has confirmed my suspicion that it is a protracted endeavour..... Previous experience has taught me to place rodent traps on all four corners. Even living in a temperate climate never ceases to shock me the unfortunate number of candidates that try to make my vehicles their abode...
