What is best sealant when replacing clearance lights

Anytime I add or fix something attached to the sides, I use the black butyl tape behind the fixture, then use an acrylic? window caulk (typical for use with home windows-flexible and durable, easier to remove if necessary-specifically, DAP Dynaflex 230 clear). The acrylic is so much nicer to deal with than silicone. Also it goes on white but dries clear, so it's easier to see when working with it. x2 about leaving a way for any wayward moisture to escape out the bottom.