dicor caulk

In talking to an RV tech friend, he said just remove what you can with your fingers and then cover over what is still there. It flows into the cracks and crevices so you dont have to worry. He did suggest taking a sharp knife and where it is cracked, widen the crack a little to ensure the new stuff flows into the crack better. He said you will likely do more damage to the roof trying to remove the old stuff.