Well, that was tricky.
I'm beginning to think that restoring a rocking horse properly is a workout for the brain - you come across so many problems you weren't expecting, to which you have to devise solutions.
Today I secured the ends of the swing irons and nailed on the brass bowler hats. I'd bought split pins to go through the holes at the ends of the irons, then realized because of their large heads the bowler hats would not fit on top. (I also had to file down a couple of the ends and washers a smidge for the same reason.) What to do? I cut lengths of wire coat hanger, long so I'd be able to pull on them. I annealed the rods, bent them to an S shape through the holes and cut them to size.
These worked perfectly. Perhaps I could patent them and become a millionaire?
I used tiny brass tacks to nail on the bowler hats. They were quite stroppy, over-compensating for their small size no doubt.
Zaphod is now finished, hurrah! I haven't yet bolted his hooves to the hoof rail - I'll have to take him home in two trips as my elderly Micra isn't quite large enough to transport him on his stand.