Trimmed J Channels to fit better with the bulkheads. Then, partially removed the J channels and removed one bulkhead at a time and fluted it to fit the shape of the skin. That worked great and I'm real happy with the fit of the aft tail section. Lined up the lines on the J channels and clamped them and they are ready to drill. Checked for twist with plumb bob and a level, and with a couple of shims, it is as good as it's getting. Fabricated (made) the small angle that attaches the 787 to the 707 bulkhead. cleco'd on the 787 for additional support. Here are the usual pictures of the aft tail.