Patrick, I use a 5 in 1 tool. You can get them at any hardware store. I cut the edge of the caulk with a box blade then use the tool to remove the old caulk. Just take your time.
Thanks Hunter 11 the wife and I used an exacto knife and razor scraper and its to easy to damage the side panels we have been thinking about what else to try.We will get one tomorrow as the back windows need to be recaulked.our trailer is new but it was on the lot a long time and the rear window caulk is cracked at the top