If you want, I can:

Before you build your "better mod PKG," understand the landscape.

Most tutorials operate in a grey area. This article is for educational purposes to understand how these systems work.

A PKG (Package) file is the installable format for PS4 games. An official PKG is encrypted. A mod PKG (or fake PKG) is a repackaged version that has been decrypted, modified, and then "Fake Signed" so a jailbroken PS4 accepts it as legitimate.