Saving Old Seagulls

Is there any more info in the Mechanics Manual than in the traditional service and parts manuals?

https://ebay.us/OkTh9n

I’ve not seen one of these before but looks like something possibly issued to a local mechanic. One thing I noticed in this particular eBay listing is a page on the alternator which I have not seen elsewhere.

Thanks

I've seen a 1992/3 one, this one looks like it has a bit more in it, but can't be certain without reading it.