Chris - the piece of plastic strip used to form the curved section of the cockpit was simply cut to length then placed inside the fuselage framework, it formed its own circular shape.
Ernie - The turnbuckles are 0.5mm brass tube cut to 2.0mm in length, I insert an eyelet into each end, these are made from twisted 0.13mm copper wire with a 0.3mm eye, CA holds them well into the brass tube.
Des.