I found a 1973 Buick Riviera in a local boneyard, and removed the 12 bolt rear end / axle and am looking for code number identification help to tell me what the gear ratio is, and if it is a posi rear end. Please help! The code numbers / letters are as follows; BN (located next to the housing), also the numbers 406208 and the three letters CFD. I am looking to sell this unit, and need this info. Thanks a million!!!!
