The other night I noticed the pilot light on one of my gas fireplaces was out. I followed the instructions to restart it but not only would the igniter not light the pilot but even if I lit it with an open flame, it would not stay lit. I tried cleaning it with a wire brush and such but no good. At this point I am assuming it's the thermal coupler that is bad. I read how easy it was to change these but when I went to remove it, closer inspection seems to reveal that the coupler is riveted to the pilot assembly. Does this mean I need to replace the entire assembly or did I miss something? Thank you!