Crap, I just did it and pitched the spare wires.
Are you planning on making your own leads? I would take them off one at a time and do them that way. I bought a set and just matched them as they came off and put the closest one back on. As always, they never fit right.
Sorry I don't have the leads, otherwise I would measure them.
Mine was a 3.9 anyway. As long as they fit, they are generally the right length.
Ed