Just got a Osburn Matrix. Thought the tie in point on too of insert "6" round" would have stuck up more then an 1/4" came with 3 small L brackets that screw to top. Question is. Do I screw the 6" stainless coupling that came with Liner Kit to that. And the liner to the coupling. And if so. Do I need to caulk the coupling around insert? What caulk? I stalling it tonight. Wanna make it right.