Zenith Rubber Manifold Sleeves?

[Stretch32]

I was looking through some parts lists today and saw a part called "Rubber Sleeve for Intake Manifold" part number 999-703-076-50 (now NLA apparently). I saw a picture of this part the other day in the "For Sale" forum still attached to a set of Zenith manifolds. My question is, what's the purpose of this piece and does it hurt not having them installed? Should I try and find a set for my Zenith manifolds? Thanks in adance,

Stretch

[chris_seven]

The PET describes them as a rubber grommet - rather than a sleeve- and 999.XXX. XXX.XX numbers are usually standard hardware items such as nuts, bolts and washers.

I have never seen them fitted to a manifold but would be interested in seeing a photograph.

[Stretch32]

Here's a picture I took from the "For Sale" forums showing them installed in the holes between the intake necks(?). There are 4 in total with 2 per manifold. If you look atthe PET it appears this is where they go so I think the pictures are correct.

Stretch

[911scfanatic]

You pass the spark plug wires through them.
Keeps the jackets from wearing through and the wires from grounding to the manifold.