Any help id'ing my rear end would be appreciated...the numbers in the pic are 358, it is in a '68 cutlass convertible, 12 bolt, type "O". I found no numbers on the axel tubes. The diff housing has the casting number - 394139. Thanks for the help!!

 

should be numbers on side of ring gear. got picts?

 

I don't see any numbers anywhere else......

 

should be on the side near where the gear bolts to the ring

 

also you can check pass.side axle tubein rear next to housing should be two letter like TO

 

I ended up counting the teeth on the two gears and devided them into each other to come up with a 2.78.....