Gear selectors

[Bonnet-rouge]

After my return from UK changing between 3rd And 4th lever is very stiff first and second ok , but going from third to second sometimes can't get there . Between 1st and 2nd moves freely. Today I started to get to selectors having read can do without taking seat box out well just won't get there so tomorrow seat box out , out of the three selectors middle one moves freely 1st and 2nd left one does not won't to move the cover is loose now any advice what to look for , have removed spring and ball from left and rught hand side middle ball bearing does not want to come out for now . It's a series 2 think an early gearbox . Before starting I left it in neutral ....