FD Engine Year ID

[Skatelement]

I Have an Engine purchaced from japan compleate with tranny one of those ebay deals you see floating around. When it arrived I was actuly shocked. I was in good shape. Clean and from what I could figure out fairly low millage. they all say 50 to 60k yea yea. But maybe I got lucky mine is strong and good compression. clutch was factory and looked to be if guessing 40k or so millage on it or I hope. Anyhow I was trying to identify what year this engine is and how. The ecu is N3A7 the AC compressor has 134a labeled on it. thats all I could find for clues. As my 1994 FD USA has R-12 compressor. Is there any numbers on the engine that might point to the year? if so where might I look. Thanks.

[Supernaut]

From what I know, the only thing you can look at are components around the shortblock. Differences in the OMP, rats nest, manifold pieces are blocked off already, I dunno what else. Aside from that, I don't think there is a number stamped on the motor that will tell you what series or year it came from.