Agree w/ Campgems- never use the screw down pivots for a control surface. I prefer the Sullivan clevises with the little clip. I would think the 2-56 thread size should be fine for a 60 size plane, though. The Sullivan clevises also have a pin that is a better fit in the holes of the control horns. The other brands of metal clevises (Dubro & GP, anyway) have a smaller pin, which introduces slop. I have used the GP brand ball links, but also found them quite sloppy. The best ball links are the ones with captured ball, where the screw actually goes through the ball. I don't like to use ball links on plastic arms, because it moves the point of force away from the arm, and introduces a twisting force on the arm. If you use metal servo arms or metal control horns, they are strong enough to resist that twisting force without distorting.