Here's a step by step: (as best to my memory and not sitting in front of the actual tools atm)
Backup your char.LGP file FIRST!
Make sure you have the .p and TEX file for the gold hilt field model, and that you have pasted them into your charLGP file, and make sure there are no conflicts by doing so.
Now, Lets say you have the default cloud model, and you are looking at it in Kimera..
Choose the chest part of the model, on the right click "add part to bone." If you don't see that option, there is an button that says "bone options" or something like that, that you need to press first, and then the "add part to bone" should be there.
Once pressed, browse to the .p file that is the gold hilt sword model in question, and it should come into kimera as a big white sword, most likely much larger than default chibi field cloud. At this point you can resize and position it however you'd like on the model, and once you have it where you want it, you need to add a texture.
If you are still looking at the "add part to bone" button, there should be a button that says "texture options." When you press that you go back to texture options and the sword should be showing no texture at the moment. So you choose "add texture" and again browse to the TEX file for the sword you copied over earlier and presto! You should now have the right sword with the right texture on your default cloud.
Save the model, and make sure you choose "no" to combining same P files. Re-encode your charLGP file, place it back in the data/field folder, and you should be good to go. If things went horribly wrong some how, at least you backed up your charLGP file first, right?