Bill,
I don't rivet any part of the forward fuse, including the aft canopy decks (there are forward decks, also) together until it's entirely fabbed, fitted, and drilled. Everything, as in "all", including upper forward fuse, instrument panel, center covers, vents, and plumbing. The tail cone and center section are riveted, but clecoed together upright on horses (not upside down per instructions). It's so much easier to fit up all the longerons, bulkheads, everything, forward of F-704 when you can take the entire fuse apart and put it back together as needed for access. A real treat is having the forward bottom skin and firewall removeable for tube bending. There are plenty of paint-yourself-into-a-corner opportunities where the instructions will send you if you go strictly by them - and sometimes they make broad leaps to leave you wondering when and what is in between. Keep your wits about you regarding tight clamping and clecoing temporary installation(s) of pieces, and removing/reinstalling repeatedly, to establish and maintain angles and fit around corners so everything continues to mate up as the structure becomes more rigid with added components. Make sure there is no fuse twist if you skip past fitting the aft deck under the emp to leave even the full-length longerons loose.
John Siebold