Luggage compartment dampers Alternating

Hello in the round, I am a bit at a loss. Wanted to change the rear flap dampers and has to find that they are so easy to install there. New damper as long as old. Number is right, but both in the developed condition by 3 mm too long. Does anyone have a tip how to squeeze them together or is there still a adjusting screw in the mechanics? Thanks in advance for your tips. m-race