The rubber ring is held in by the force it is under, nothing else is required. It is dit is very difficult to put these on properly, esp the end on the a/f housing. It is usually pressed on with the filter housing held by another person, or clamped in a vise. Then the whole a/f housing with U tube is put on over the turbo inlet.
You could probably use some help in putting on a new ring.
I ordered new rings (gaskets technically) but wish I had used the old ones, because there is a ring on the metal snout of the housing that leaves an indentation in the gasket after some time, and it is easier to use an old gasket then a new one because of the groove that ring leaves in the gasket.
I hope that wasn't confusing
