The one you have look like this one?

 

 

There is nothing missing, take your old one out and install this one.
Put the hose on the pipe, stick the hose in the pan.
Small washer goes on the shorter pipe. it fits into the intake manifold.
Install the 2 bolts and you are done.

Be sure to clean the area of the pan of sand, dirt, grime etc... so it does
not fall into the hole.
With my 86, it had an older style CDR with a long pipe. There was a rubber
grommet in the pan the pipe fit into. after 30+ years it was as hard as a
piece of plastic, and removing it, pieces broke off as I removed it, some
dropped down into the hole and had to fish them out with a needle nose.

Also had to use solvent soaked rag to wipe the dirt and grime away from
the hole before removing the grommet.

This newer style is an up grade over the old one. But the CDR still works
the same. The price has gone up a bit, I paid $77 for mine.

EDIT: Did some Googling and came across this picture from Diesel Hub.
old and new style CDR



I did not read the article. This picture kind of looks like the guy cut off the metal tube from the old one
and is fitting it to the new one.

But you get the idea the old one had the long metal tube like the right pic
and the new one has the short tube as the left pic shows.


Charlie.