How can I tell what year my motor is???

[Xemu]

Trying to find a clutch kit that will fit my flywheel.My motor and tranny came bolted together so if I find the year of my motor I will know what year flywheel and I can go from there.Only it's not that easy,the original D16A6 Si head was sold and a D16Z6 head was installed.My question is:Is there a way I can tell from my D16A6 block what year it is???? Thanks guys!!!

If it helps at all I have a 20 spline tranny.

 

[Xemu]

If you have a 20 spline transmission it's '89-'91.

I kniw that but it doesn't do me any good to tell me I have either an 89,90,91???? I need to know how I can find out what year I have not what 3 years I might have??? Thanks