With the help of some photos from Kerry Fores at Sonex, I got the super tin in place. I was trying to put it on (see photo 3) with the bottom of the tin at the base of the cylinder. But it actually goes on several fins UP from there, so that the top-most horizontal surface of the tin, rests on the top of the BLACK cylinders.
Finsihed putting the head and pushrod tubes on one side of the engine, then put the last 2 cylinders in place, followed by the super tin and the pushrod tubes, and finally the head. Everything torqued in place.