To be honest, I was thinking of a second laptop on a cart, with a bunch of cables hanging out of the back end of it. Possibly four laptops (TFS mentions VMs running XP so any brain-dead 32nd-hand laptop should have the necessary grunt) on a cart so you can do an entire island at a time.
- set out the cones to stop new cars arriving at the target island then hook up the cables as existing drivers finish and leave.
- set upgrade running on first system to be ready. When you're blocking on that pump, swap to starting the process on the next available pump ; lather, rinse, repeat until all 4 are running away.
- meanwhile, start moving the cones so the first machine to be finished will be the first available to the next customer, and you're ready to start isolating the first pump of the next 'island'
If you can spread things out evenly, then your maximum hanging around time has dropped to 7 and a half minutes, and if there is any significant amount of user input, your idle times are going to be shorter than that.
Though it is a networking problem, it's really an optimisation issue.