You can find photos online of factory lenses and the rubber boot(s) that cover all the holes. I think once you fill with water it will be painfully obvious where the water is leaking in and quite solvable. If it's a really tight seam or in a corner you may be best off with 2-part epoxy clear coat


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2011 E70 • N55 (me)
2012 E70 • N63 (wife)