Went soooo well. The farrier pulled in just as I was going outside to give the shot. We waited about a half hour on the stuff to kick in, while the farrier just stood there and talked and then knelt in the paddock with us for twenty minutes, waiting on Siaga to come over and sniff him. He was so patient and so kind.
Once we got started and the tranq had kicked in, I was able to lay my head on his neck, close my eyes, and just hold my hands under his chin to keep his head up. He was that calm. Which was awesome.
Also, he learned part of his lesson, he was still with it enough to think and lick and chew at me and the farrier while he worked.
Turned out that the limp problem came from the sole as it was splitting and peeling off. It wasn't as bad that day, but must have been the riding that caused the chips to split further. No thrush, no abscesses, just overgrown sole. I'm expecting it to take a few days to a week for him to stop feeling tender footed, so until then, no riding.
Here's to hoping that the next round will float along much smoother than some previous ones, and won't need as much of the tranquilizer.