Hi Dave, couldn't find Vulkem 911 in Reno on Friday but did find an equivalent. "Sikaflex 1a" Polyurethane sealant". Has all the same properties and performance as Vulkem 911. Now for the million dollar question. Is there a trade secret for removing the old polyurethane sealant? Over the weekend I have tried using a sharp utility knife, a high speed burr, chemical softening agents, other tools that will not be named and bad language, nothing penetrates this old stuff. I have searched the Internet and found solutions that involve heating and scraping the caulk, cutting the two edges with a special diamond blade ten pulling the caulk out, and more chemicals that are suppose to soften the old caulk. What am I missing? Thanks.

Kind Regards,
Scott