there was a post up the other day that had a link to another site with all the diff options on sierras and mk3 granadas,i cant remember what one it was to try and find it,what i want to know is can i swap the drive shaft cups from an xr4x4 diff onto a 2wd diff so i can use the 2wd diff in the 4x4 beam with the 4wd rear shafts,also what do i need to do to the diff/beam to fit the 2wd diff