I have the front 4.62 third out of my samurai and I'm wondering if there is a way to tell whether the locker uses the stock side gears or the couplers ?   I can look in the  splines but i don't know what to look for or if there is a noticeable difference.   If it uses the side gears i'm going to put it  in  the back but if it uses the couplers i need to find another 4.62 to set up for the back. ( Just removed a hybrid rear end ) Currently running 3.73's  open front and rear. I don't want to tear it down untill i'm sure i don't want to use it.

the ones that reuse sidegears are tapered on the outside like the sidegears.
the ones that have the couplers are flat on the sides.

Thanks . I'll check that out when i get home from work.

Just to clarify......with a samurai carrier, you can't tell from looking in the end of the carrier.....you will have to remove the endcap.  And there are no holes in the side of the carrier for you to look in either, unlike a trackick carrier, where you can look in the side of the carrier and tell what is in there.

  I'll take a picture of it in a little while . It may be a stock tracker front housing but i don't know the difference

  I'll take a picture of it in a little while . It may be a stock tracker front housing but i don't know the difference

A trackick front third is aluminum.  A samurai third will be steel.
If you are talking about carriers (what the ring gear bolts to), then a samurai one will be solid on the sides (no holes/windows) a trackick one will have holes/windows in the side where you can see into the spider gear area.