have a look in the base of the basket and you will see a hole, you need to insert a pin punch or phillips screw driver and lever it slightly one way to move the cush drive at the back so the teeth line up so it will slide on the rear gear, make sure the oil pump drive pins also line up when you push it home
thanks ozrider that made it easier -so obvious that you need to align that rear gear,just had a major brain dead moment. have to back off the bongs whilst doing repairs in the future