You might consider contacting "The Yard Store" in Wichita, Kansas. Being an aircraft manufacturing town, Wichita produces a lot of aircraft surplus tools that can be purchased at the "Yard Store" ( an outlet for the old Beechcraft Company to sell surplus tools and materials). They sell a need little rotory bit, you can chuck into a drill, that will remove sealants and caulks of all types. It is made of a material that is not as hard as aluminum and will not scratch or mar the finish of your Airstream, while it cleans the sealant and caulk residue from seams and joints. Very Cool!!
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