I used a dremmel like tool with a tiny flat cutting bit. Lay the hook in place. The eye of hook will overlay the spot machined for the normal hook. I then used the bit to enlarge the eye socket so it would fit. You have to do each side. Once that is done and your hooks lay in the groves and the eye is in position with all slots loaded close the mold. Here is where it gets tricky, it should not want to close completely because of the larger diameter of the hooks but you have to make sure when closing nothing got out of align so you need to check a couple of times. Then when you are at this point you need to clamp the handle with something that will hold it closed, then place mold on a solid flat surface and tap the up side of the mold with a rubber mallet or leather one. Not real hard, just back and forth until mold closes up. The aluminum is soft enough that it will open up the hook slots so that the hooks will lay in there properly and everything will be aligned when you pour. Pouring pony heads can be frustrating at first, putting in the swivels then hooks and trying to close without anything moving but isn't bad once you get the feel for it. If you need any more help just give me a call.
Proud Member of Team Geezer
Charlie Weaver USN/ENC 1965-1979