The old site search from Google needs to be updated. Use the Search at the Upper Right, or use What's New in the center - it has a drop down arrow. You will need to change your Favorits by right click mouse and clicking favorites. Many of the posts in How to Use This Web Site are old so the links may or may not work. I have one hell of a lot of work to do!
Can't give you much specific information on your particular engine, but general specs for that model are as follows: ACN
2-5/8" Bore x 2-3/4" Stroke
6.0 HP @ 3600
Replaced ABN and AKN for greater HP.
"D" in model indicates Stellite exhaust valve