OK, last question (not!). The green external 2 to 1 exits the mast, goes up and around a block on the tack of the main and down to...what? A clam cleat or an eyestrap on the mast? That would complete the last 2 to 1 cascade, right?

That means there are 3 exit blocks on the mast, two that lead through the mast, into cleats, and on to the sailor's hand and a third for the green to the tack cascade.

So the entire inventory of needed hardware is

1) a double block on the crossbar
2) a single with becket for the green to red
3) a single for the blue internal
4) three through-mast exit blocks
5) two cam cleats
6) stainless bolt and tube for the crossbar.
7) clam cleat or eyestrap for the end of the green.
8) appropriate lines.

Sound about right to you folks? Any of those blocks need to swivel?

Pete, thanks for the 62 inch measurement (1575 mm). I would never have guessed it was so far up the mast!