Is there one?

Basically, I have an object that has routing slots all around it, but I want to place it against a wall, so some of the slots will be inaccessible. At the moment my sims piss me off by whinging about the inaccessible area before choosing an accessible part, so I want to remove the inaccessible slots altogether.

Just deleting them made the object crash my game, so I need help. Does anyone know of a tutorial for this?