My Gearbox Lupo 1.7 SDI has just given up on 4th gear all other gears select fine and drive 4th can be selected but theres no drive (just like neutral) Is this down to the lay shaft bearings that i hear so much about if so, I am an Engineer, is it possible for someone with a v good fitting background to repair this gearbox once removed from car, if so where can i get best drawings/manuals cheers todd south wales