I have my great grandmothers cast iron cook ware. Its over 100 years old and the frying pan I use the most is showing signs of crusting up. I want to clean it down and re-season it. Am I correct in that I can build a fire and get it hot enough to burn the junk off and clean it up with a wire brush and then re-season with lard. What temp should the oven be to reseason. Thanks.