Have just put some new carbontex washers in my mates 200DHSV and when putting back together, i can seem to keep the level wind to stay in its right place

, is there some sort of lock that stops it moving back and forth? One side has a washer and c clip, the other side has a plastic type clip and a plastic gearing that sits inside it. It looks and works well until you tip reel on its side and then the level wind falls out from the plastic gearing side
Can you help?
Cheers
Kevin