First, thanks for any assistance with this issue. I have a 1998 Coleman Shenandoah. I bought it with the knowledge that the roof was sagging, but I wasn't told that it was leaking. When it rains the ac unit leaks to the point that I have a steady stream of water coming from it. I've been told that I need to reseal the ac unit, so I bought a sealant strip with a sticky side from Lowes and I've removed the ac unit from the roof, but now i'm unsure where to put the sealant. It seems that I can either put it directly around the square opening that the ac goes in, or I can put it around the outside of the ac unit. I'm very new at all of this and I got a good deal on this camper with the understanding that it would need a little work, but I don't want to mess it up. Thanks again for your assistance.