Shoe,

I ran some numbers your proposed setup will provide .15 slack in the slack cable and provide .24 tension in the pull cable at extremes.

Best case setup would be to eliminate the rearward offset at the rudder control arm (center the cable pivots over the hinge-line), and use equal length arms 4.25-4.25, there is about a .05 differential in cable lengths at extreme throw with this setup…

Rudder deflection will be 1:1, 60* servo angle will net 60* rudder throw.