How to use UnrealPak (Or similar) to remove files from pak file


I basically want my user base to be able to create custom pak files for my game. The problem is that when the player does a File>Package the final Pak file has the engine content in it which is 64MB, and I don’t need those. I only want the content inside of “content” not “Engine”,

So, is there is a command or parameter that I can use with UnrealPak.exe to remove a folder from the pak?