Step 1: Mark the top mounting point. When placing the gas spring, you can start at the top mounting point, which is about 1/3 the length of the lid from the hinge.Step 2: Open the lid to the angle you want to mark on the bottom mounting point.Please note that when marking bottom mounting points, the post does not need to be completely vertical. The angle of mounting of the gas strut is important.Step 3: If the adjustable lid cannot be lifted, the top mounting point can be moved 0.79"/20mm toward the lid hinges (0.79"/20mm) each time.If the lid cannot be closed, the top mounting point can be moved to 0.79"/20mm opposite side lid hinges (0.79"/20mm) each time.Note: Bottom mounting points must be adjusted to fit the moving of the top point