Really glad I kept the 600 boom parts, no way I am changing down and have a spare set of 700 parts in case of a boom strike etc. So putting together the N5C at the moment and it occurred to me that the parts might be useful. The boom and torque tube are longer than the N5C, but thats great, easy to cut down with careful use of a dremel to make N5 spares!
My tip for a nice true cut on a tube is to wrap and tape some A4 paper around the boom and as long as the end of the paper wrap is aligned and straight, you have a good marker for a dead straight cut. Used to do this on much bigger yacht masts, saves a lot of anguish.