The direct connect collar for the Harman Magnafire Elite coal insert is a bit different. Has anyone used a sealent, gasket etc. when installing one of these? As the oval liner just inserts into the collar and the collar just rests on the top oft he stove, I am not comfortable with the design. Has anyone done one of these? I have the pin for the liner. What concerns me is the lack of closure where the collar meets the stove.