We just bought a house that has a VC Defiant Encore 2190 stove. I am in the process of replacing gaskets and have a question about the upper fire back. It looks like it was cemented into place but a stove shop said it uses a 5/16 gasket. Do I use cement I put a gasket on it before bolting it on? It looks like it was previously removed so I wonder if they just used cement instead of putting a new gasket on it.