Unscrew both sides of the primary throttle spindle. You really need to remove the bracket, springs etc. to check for play in the spindle
Right side.
Now you have removed these gently wiggle the spindle shaft around. Mine had quite a bit of slack in in. I took it to a carby specialist, he reckoned it was OK, he'd seen carbys with twice that much slack in them with no ill effect( it would only effect the idle anyway).
To remove the spindle shaft you'll need to unscrew the two screws on the butterfly flap. It will then slide out.
You may need to remove the burrs on the spindle shaft before you can remove it, with a small file.
The spindle **can't** be rebushed due to the design of the carby body. So I just greased mine well and re assembled.