> Payload Extractor is a utility that opens Mac OS X .pkg files, the
> same files opened by the OS X Installer application. But unlike the
> Installer application, Payload Extractor allows you to decide which
> file(s) you install and where you install them.
>  For example, you could use it if you needed to replace only one
> damaged file in an installation, or if you wanted to install another
> version of an application without installing over the previous
> version.

#1: *v1.1 Universal
#2: v1.2 Intel only

For mpkg archives goto: <https://www.timdoug.com/unpkg/>

Compatibility
Architecture: PPC x86 (Intel:Mac)

Mac OS X 10.4-10.8
PPC or Intel.

*credits to @Church of PPC Punk for testing.
Also 10.4 tested on G5.