3/S rear differential discussion, the "H", "G", and the "J" specs, is it JDM, US, UK?

[IPD]

as far as US Spec stuff goes with interchanging.... the JDM 6spd transmission uses a US Spec 5spd rear diff. The JDM ATX AWD trans uses a US Spec 6spd rear diff.

which would make the only "oddball" of the group the USDM 6-speed rear; which is the same part as the atx rear.