[Leon Crampin]

If you look carefully at your first picture of the inverted upper chassis, the unidirectional "spring" (actually a handed wound steel tape clutch) is protruding from the bottom of the intermediate pulley assembly.

These "springs" are handed and need very careful handling to avoid getting distorted, thereby becoming unusable. There should be a minute amount of axial play in each assembly - there may be plastic thrust washes, but I can't fully remember. The springs are a very precise fit in each bearing assembly, and the sintered iron bushings need light oil applied sparingly. There are also sintered bearing bushings in the lower and upper turntables.

Leon.