Check the toymods thread regarding the corona disc conversion, however i'm fairly sure you use the TE72 bearings. There shouldn't be two listings for the TE72 as they used the same differential for the length of their production run, i.e. early and late TE72's use the same diff.
Cross reference the part number of the bearings with the part number for an RT132 Corona differential, these also use a T series.
Use those bearings.