What year and model number is my evinrude 28 SPL

[Robin]

The ID tag is missing. The serial number from the freeze plug looking thing is R8170838.
Looks like the pics I've seen of 1989-90 28 SPL motors. Dark blue.

 

[user 21074]

Is there no model number on freeze plug?

 

[Pappy]

The number on the freeze plug will not get you anywhere unless there is a model number above it. By the time the SPL engines came out I believe that practice was done.
Your best bet is what you have already done by looking at reference engines on the web.