Hey all!
I seem to be having trouble with this...
I'm going to the correct directory, but for some reason the icns files I am looking for do not exist there. It does seem to have just about every other icns file, including those for older Mac models (G4s and G5s mostly), but no Mac Mini, Macbook Pro, Mac Pro, etc... and I want to change the Mac Pro model.
Is it possible they moved it in 10.7.4?
Edit:
Ok, so it seems these specific icons have been hidden. Looks like Apple is on to us.
Now to figure out how to un-hide them so I can change them.
Edit again:
Easy terminal command:
defaults write com.apple.Finder AppleShowAllFiles YES
Now you can see them... but you can't replace it because it's still deemed "invisible" by Apple. No worries, you can just delete it from the folder and replace it with your own version (save a copy somewhere else first just in case!).