Hi everyone. In the process of searching for an insert for my old fireplace. Unfortunately I did not install this one as it came with the house. House was built in 1985. I was told I cannot put an insert in unless I have the UL listing of the exiting fireplace. I have attached a few pics. I did find 2 riveted plates on the door housing. I tried cleaning them but the only identification I can find is R62185. Nothing else. Any and all help would be greatly appreciated.