You will now need to fit the two Tunnel frames (parts C) one to each tower. Only build the tunnel
sufficiently to locate the 2nd tower and check all sides are level and upright. Once you are satisfied
that the second tower uprights are vertical in both planes (using your spirit level) and the platform
horizontal, proceed with construction. (if you are planning on taking a break at this point you may
consider concreting (Post-Crete) the towers.
TIP: To align both towers in as straight a line as possible build as above then before concreting stand
back as far as you can to get a view of the four uprights on one side. Move the 2nd tower as needed
until all four uprights are lined up.
*Now repeat for the second tower*
Attaching the Tunnel: