You move the two damper shaft mounting screws to the alternative positions for short shafts only to be able to install the MP-V over a damper shaft with an exposed length that is less than 54 mm (2.125 inches) but greater than 22.2 mm (0.875 inch).
Remove the two damper shaft mounting screws from the MP-V actuator collar using a 1/8-inch hex key.
Remove the actuator collar.
Press and hold the manual override button and rotate the actuator counter-clockwise (CCW) until the two screw holes for short damper shafts (alternative positions) become accessible.
Install the damper shaft mounting screws in the two screw holes for short damper shafts.
When using the alternative positions for shorter damper shaft lengths, tighten the damper shaft mounting screws to the following recommended torque:
Steel damper shafts: 4.5 to 5.6 Nm (40 to 50 lbf.in)
Aluminum damper shafts: 4.0 to 5.1 Nm (35 to 45 lbf.in)
You can now install MP-V.