My 4 is "only" 29 Yrs Old, but I have found that it requires much less force to get the second notch of flaps on if I get the IAS down below 80 Kts first. In fact if I try to deploy the 2nd notch of flaps and feel a high resistance to moving the handle, I check the AS and lift the nose a little to get it there.
Having said that, I did add a .060" thick plate to the outside of the 2nd notch block on the side of the seat a few years ago. It creates a ledge for the flap handle knife edge to bear against when the flaps are deployed. I did that mod after the flap handle slipped out of the notch on a landing. Landing came out ok, but surprised the heck out of me when it happened.