Re: What are the correct manuals to buy
Get the Seloc manual for the engine. It'll cover the available drives for the year range the book covers. They aren't the end-all be-all of manuals, but they're pretty good. You can get them here at iboats (it's where I got mine), and I also got the online access to the book.
Here's the link to your book. If the link doesn't work, search 'seloc' in the marine store, yours is on the second page about half way. I found the online subscription to be somewhat handy, in that when I'm bored at work and daydreaming about the list of things to do on the boat, I can reference the manual. Some folks print out the page(s) they need for the job they're going to tackle, and that way they don't get the book all dirty.
The shop manuals are the best, but really expensive, and for some (myself included) they are overkill.