As long as the current hubs are not vastly different I can do fine tuning later. So I guess we're looking at a little under an inch of travel, and less than 2 pounds required to shift.

The reason I need to know this is so I can buy the correct servo for the task (I hope you can see where I'm going with this). It's pretty easy to get a servo to pull ~1 inch of cable at 32 inch pounds (Where A is the angle of servo; L is the length of cable to some center point; length of cable pulled = sqrt([sin(A)^2]+[(L-cos(A))^2]). Now I think I'll be free to get the fastest servo for the job.