Mine has the rust mod and the pulled drain plug mod already built in. Like in most Hondas, it is most likely the taillights doing all of the leaking. As posted previously, window weld (3m stuff, sold in rolls @ Discount) is a great idea. Pull the lights, put the stuff around all openings on the outside of the car and then seal the inner part with silicone. Them bitches will never leak. If water still accumulates, take the back seat back out and crawl in the back trunk w/ a flashlight while someone runs a hose on the trunk area. You should be able to find and correct it then.