honda 8hp year?

[jancsikoerber]

I recently bought a 8hp honda-on an old alumi 14ft v hull jon-a 1961 -with a new trailer-great deal 475.cash---I have no idea the year of honda the numbers on trasom bracket are 1000584? they started making this in 1987 and was told the numbers put it in 1987-1998 surely there is a way to get closer--!! any body have any clues? the owner-believes his father bought it in early 1990's not sure if it was new or used-also it is mounted on a "minnie jacker" because it is long shaft. altho still a few inches below bottom of rear of boat--can I raise this "minni jacker" more on the transom-without some other kind of center of gravity issue or some other delema??