Alas bottom line is, you can't! The street cabinet has, presumably, been installed on public land and with the full approval of the local council. Even if VM could be persuaded to move it, this would also involve considerable expense and inconvenience to everyone who is connected to it, who would all expect VM to compensate them for the loss of service while it is moved. All these expenses would come back you, you may well be looking at a few thousand pounds!
The street cabinet also needs to be sited within certain distances of properties as the cables linking the cabinet too the houses can only be uptown a certain length, which means that probably the cabinet has been put in the optimum position and can't just be moved somewhere out of the way.
I'm sorry to say that realistically, you need to forget about this as moving it just isn't going to happen.
