To Remove Steering Shaft
(Before you remove the chain check for any play in the key securing the chain sprocket to the wheel shaft.)
First slacken cables at the steering Quadrant. Lift chain off sprocket wheel and secure temporarily (say by hanging on a piece of string).
Remove circlips on inside and outside of shaft and lift out shaft key (see picture below) locating chain wheel to shaft
Chain wheel can then slide off shaft inwards (forwards)
Which allows shaft to slide out aft.
If any play in steering renew key.
Reassemble by replacing shaft, sprocket, key, chain and circlips.