An easy way to tell is look at the back of the diff housing. The 8 is smooth and almost spherical, with two dimples sometimes. The 9 has a large vertical bulge. Also the overall shape of the 8 is oval where as the 9 is more round. HTH
65 Fastback 289 4spd in storage :-(
91 CRX Si... A.K.A. my go-kart with AC!