Real deal or move along?

Also realize that the 8 1/4" axle will have the larger bolt pattern axles, and swapping to it will make a mismatch with your fronts. This is not a deal breaker, but may cause a problem if you have a flat, want to change to different rims, or other issues of the like!

I would also confirm the ratio of the gears in the 8 1/4" before I bought it, as there are 2 different sized gearsets between cases, and the higher 2:40-ish case will not interchange with the lower 3:21-ish gears, limiting you to highway gears only!