That's a good one, liam548, because it can be solved only if you are able to 'see' the vectors, over the wind computer, rather than applying a series of obscure steps (Keygrip's estimate makes a lot of practical sense, though).
You use the wind-down, right? So the HDG/TAS vector will lie on the centre line, starting from the origin of the fan lines and ending onto the centre dot; you can then set the HDG under the index and the TAS under the centre dot. The TR/GS vector will start from the same point, lying on a fan line 3° to the right of HDG, and end where it meets the circle equal to the GS. Clearly, the latter is also the point where the W/V vector ends - if the triangle is to be closed - i.e. it's the wind mark, which gives you wind direction and speed, by whizzing the wheel as usual.
By the way, the Confuser does get it wrong, sometimes, like when it says that the properties of a gyroscope depend on its rotational speed and centre of gravity. Yeah... that makes sense.
Deeday