This "hydraulic damper" is really a gas filled strut. When it gets hot - in the summer - it becomes harder to close. When it gets old, some of the air leaks out and it becomes less effective. The torsion arm you have, supporting the hood, is much better: It is lighter and does not wear out. Cut yourself a slender piece of wood to insert when you work under the hood for a prolonged time. Insert it into the square hole for the latch and make it long enough so that it reaches the channel below the air intake. Put a piece of felt under it. Glue it to the wood. The existing arrangement is much better than a modern air strut. Often, what's new is not better. And yes - you may deform the hood using an gas strut.
1969 280SL,Signal Red, A/T, P/S, A/C, Both tops. Ret. engr. 1967 230SL - Sold