I'm sorry, kscevior, my manual collection is on the boat. I've just had a total shoulder replacement, and I'm wearing a boot for Achilles tendon issues. I won't be down to the boat until spring, by which time I'll be fully functional...
You need to know your engine's model and build number, as well as the rest of the serial number. Spend some time on line looking for the few manuals that can be found. I've downloaded a 1982 and a 1988 workshop manual, a 1978 and a 1994 owners manual, a 1987 brochure and a 2009 serial number guide. There are sites that claim to have manuals for money, usually Pounds, and there are sites that claim to have manuals to download for money or for 'joining' their service. Also watch eBay; I've purchased parts manuals and workshop manuals but for the wrong 'build'.
Of course, decent Perkins parts emporia should have manuals, but you cannot look over their shoulder.