*37 Pickup Door Latch Problem*

[zippi]

Ok guys....I'm seeking help from the experts. I am trying to make one good door latch from two that I have. The two square holes in my old door latch were rounded off. The two square holes in the other latch that I have are really good. Here is my problem, the square shaft from the door handle goes through the latch from the side show in the pics. The square holes that you see are stationary and the one on the back side rotates. When I turn the door handle it will only move as far as the slop that is in the square hole shown. How do you get the full ranch of motion out of the door handle when your putting a square peg in a square hole??? Any help would be greatly appreciated.