In addition to counting the ribs - there should be a part No / Code No stamped on the transmission case.
For my 3 rib case the No is CA 095 74 71 [ i.e. it is a CA Code transmission - probably built in 1971 ]
When ordering parts it might help to quote this Code.
Often these old vehicles no longer have the original transmission installed. So quoting the vehicle year model, chassis No and Engine No, might not define the transmission currently installed.
Cheers Grant
For my 3 rib case the No is CA 095 74 71 [ i.e. it is a CA Code transmission - probably built in 1971 ]
When ordering parts it might help to quote this Code.
Often these old vehicles no longer have the original transmission installed. So quoting the vehicle year model, chassis No and Engine No, might not define the transmission currently installed.
Cheers Grant
1971 Sopru aka Doob