Congratulation! But, um, where are the pictures?
I too have an A4, 46 years old, well used and still going strong. The previous owner planned on replacing it when it died, but after waiting for 20 years he finally sold the boat with the spare engine, half rebuild because the original never died, so he never finished the rebuild on the replacement
Oh, and it's "Raw water cooled", lived in salt water all it's life. Man, just can't trust those raw water cooled engines eh?? Rust right through in no time. What a dumb idea...
Don't get me wrong, it is running like a top, but tops do fall over all the time, so I never quite understood that phrase. It has died on me plenty of times, but so far it has been just the basics, dirty plugs (it runs a bit cool in the PNW waters) corroded wires (Planning a rewire soon) and other minor maintenance issues. Sure, you do not have plugs or as many wires on a diesel, but you do have injectors to clog, air in the lines to bleed, and other issues.
I am also working the rebuild because I am a realist. A 46 year old engine of any verity is likely to go soon, so hopefully the rebuilt one will go another 20 years or so.