I really like resoursepacks that have CIT renames for various items, because it's a really vanilla-friendly way to add some variety and depth to the already familiar items.
However, they usually only contain definitions for Minecraft's native
items (and that's absolutely expected), and I don't think there is any
in-game way to use those cool CIT renames for modded gear. This script
iterates through all of the *.properties files of a resourcepack,
and adds more items (see above) to the items= array of each texture,
based on some really simple guesses.
Tip
The items.nuon file also contains some additional information.
Caution
You should read the source code of any script from the internet before running it, this one is no exception.