. . but that takes a second cable. This machine has a second cable available if it's serial interface is no longer used (I'll have to check), but I may eventually have to do this for other PCs there and some might not have two cables available. so I was wondering if I could find a single cable solution.

On the other hand I pulled two cable to every workstation when I rewired this place 3 years ago, so it might work out OK.