John i would not look under a NON genuine RS 2000 to look at a holden torana banjo diff.
If you GOOGLE holden torana banjo diff and look at the photos you will see the part number on the front of the diff
as the same as the photos Wiggy333 has posted.
John not all Holden diff cases were the same But you would know that as you know all.
Cheers PJ