You can order the necessary bits from a yacht chandler. They will cut wires to length, then you can use adjusters to take up the slack.
However, these are frowned upon by many people due to potential safety issues, so if you have them fitted whilst driving on-road, prepare to be criticised. I'm also not sure they're legal - it's been discussed here before but I don't think there was a conclusion. However, if you sliced up a pedestrian, I think your insurer, plus the law courts, might take a dim view.
If you come up with a way of detaching them, that may be the best way to avoid problems. That may be what you were planning to do anyway.