I think what you should try is move the cable end into a hole nearer the TPS's pivot (to increase its range relative to pedal/cable travel) then adjust the cable length to get 0.6V at idle position. Try WOT and see what the voltage is there.
Keep shifting the cable end mounting hole until you get 5V at WOT while retaining 0.6V at idle position.
Keep shifting the cable end mounting hole until you get 5V at WOT while retaining 0.6V at idle position.