Hey guys I recently just got a b16a and am looking for some info on it. Its OBD0.

For the year the stamp on the block above the #4 exhaust header says 89 meaning its out of a 1990 car (honda stamps one year later right?)?

How can I tell if it was originally auto? right now it has a new clutch so cant check for a flexplate. Has GSR cams so cant check the cams. Has a skunk 2 intake manifold so cant check that. Has a manual PW0 ecu. Is there anyway to tell? Is there anything else that would be different?

Also can I get any info about the engine regarding the numbers under the b16a stamp? What do those mean?

Thanks