Hi-low gear linkage

After having trouble selecting hi to low gear ratio I decided to have a look at the linkage it seems that the end of the rod was loose were it fits into the yoke after tightening it up I realised that the yoke has opened up and the linkage came loose again, should there be a washer or something there and does any1 know how I get to it as I can't get in with a spanner as it's just under the panel under the cubby box! Do I have to remove this? Not a big job I hope

Sorted the linkage out, but it seems very very stiff trying to change from Hightower to low ratio, I think this is why the linkage is coming loose