Rear drive shafts

[DaveyB]

Hi, could someone confirm i have this right if i come across a diff that is none lobro does that mean that the drive shafts push into it ?

I have seen some drive shafts that look like they bolt on and some that must push in, and i have seen a diff but it is none lobro i am not sure what that means. should i try and get a 3.6 ratio or 3.9.
sorry to keep going on about this
thanks for everyones help

Davey B