I originally tried that. But when ever I went to compile it still kept referencing the ServerPerksV4 package even though I had removed any reference of it.
In the end I just wrote a new perk class as a separate package and entered that in the config of the ServerPerksV4 package.
Works like a charm.
The only problem I now have is that I want the levels to scale to 100. But there will be the problem of the stars. As it will go Red 1-5, Gold 1-5, Green 1-25 and thats it. I'd like to have it go 1-10 stars and a different colour per star. That bit I'm stuck on.
Did you replace inside all the files what package they will point to (being your new package name)?
Plus if you need help with the new perk textures (including stars) I can help you out there as I recently have just figured this out myself. This will need you to make your own version of the package though so it'll affect the whole of the mutator.