Ron,

agreed the horns don't place themselves properly to get the pivot over the hinge line. I place them in the right location to get the pivot over the hinge line.

Yes it is possible to be off small amounts and I can say that I'm usually off a little here or a little there. After all we are talking about wood, foam, plastic and aluminum. The builder must put the connection point in the right spot.

These horns allow you to put the pivot in the right spot as they offset the connection point forward of where they attach to the surface. Just like anything some people can break an anvil with a rubber hammer. I know a couple of them. And I think I've done it once or twice myself. I never meant to say the horns were self aligning. They are not! But neither is any other horn on the market. Perhaps an adjustable one would be cool. I'll see what I can come up with. I know a good machinist guy and we can design something and see if it works. Who knows it may make life easier yet again. There is always a better mouse trap out there.

There are other ways to do it too. The bolt can got in at an angle, or there are lots an lots of other options. This is the one I choose. Never failed, never broken, survived mid-airs and crashes. They are light and strong, the plastic base is easy to install. Since I have never had a problem with one I chalk it up to the fact that I save time installing them. The other thing is if you need to move them they are easy to move even after the surface is covered. Just fill the old #2 holes and drill new ones the plywood plate is bigger than the base of the horn.