Hello Russel, I believe the small adjuster rods should be straight. Also check that there is no excessive play in the lower rubber bushes (the ones fitted to the gear change column arms). Any slack in this area will lesson the amount of movement the rods will have to engage a gear. Hope the picture helps, kind regards Charles GoughGear linkage    
#7306

Hello Russel, I believe the small adjuster rods should be straight. Also check that there is no excessive play in the lower rubber bushes (the ones fitted to the gear change column arms). Any slack in this area will lesson the amount of movement the rods will have to engage a gear.

Hope the picture helps, kind regards Charles GoughGear linkage