XXX-S and XXX-4 front and rear diffs

[Alexi]

Hi, as some of you may know I need to rebuild at least one of my diffs.

I have found the following for sale at my lhs:

Red alloy solid front diff (XXXS)

I realise that as a locked diff it will affect the way the car drives (this doesn't bother me though). Will it fit in the front or rear of the XXX-4? I have the original XXX-4, are the front and rear diffs the same? As on my car, they appear to be identical, but I know the G+ is meant to have different diffs front and rear.

Thanks in advance,
Alexi