Repairing a leaky bathtub spout?

Hi All, First time poster here and I've got a project that I'm planning on working on this weekend. We have a peerless single handle shower, shower head, and spout in our bathtub and the spout constantly drips water. The shower head doesn't leak, the handle doesn't leak, but I can't seem to get the spout to stop dripping no matter what I do. I've read a variety of different things on this issue from replacing the o-rings and springs to replacing the cartridge. Can anyone shed some insight or point me in the right direction? I've bought this repair kit already... Danco 88103 Repair Kit for Delta/Peerless Single-Handle Faucets - Faucet Trim Kits - Amazon.com (http://www.amazon.com/gp/product/B000DZFVPG/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1) I plan on installing it this weekend. Is there anything else I should be looking for or trying?