Unpack Sausalito PKG file

From CobaltFAQs

Most PKG files for Sausalito machines are encrypted tarballs. You cannot just open them with

 tar zxf Filename.pkg

like you can for RaQ 4 and before.

To open the PKG and see what's inside it, do

 gpg --decrypt --output Filename.tgz Filename.pkg
 tar zxf Filename.tgz

Alternatively this can be combined into one step:

 gpg --decrypt Filename.pkg | tar zxf -