Does anyone have a copy?

Good question, I want it also!

Good question, I want it too !!

In The Coronet Archive. Search Document type: "Manual" and you will find them there.

I tried that when I first joined, 0 hits.

I just did it. All manuals are there. Choose Document type: Manual. Not as a searchword.

No (see image)

Don't choose 31 aft cabin. Just search Manual.

The archive is my first option for searching, but I also found nothing!

113 hits. I can't understand what you are doing wrong.

As far as we know, Coronet did not produce manuals for specific models, and we have only found three manuals, one from the late 1960s (42 pages, probably produced 1967), and two from the first half of the 1970s (29 and 42 pages, respectively, probably produced 1973 or 1974). The text in the manuals is general, without specific reference to particular models, such that the manuals could be used for all (or most) of the models at the time. The two manuals from the 1970s should be relevant for 31 Aft Cabin, at least for boats built 1973-1977. If you search the Coronet Archive for Manuals without specifying any model, as explained by Fredrik, you will retrieve all three manuals, 29+42+42=113 pages. If you search for Manuals for a specific model, you will get 0 hits, since there are no such manuals.

This public manuals I found, but not specific for a 31 AC, after your explaining Iknow why.