On my new to me 1997 Performer that I am rehabbing there are some chips in the porcelain on the outside of the bowl and the lid. They are not too big, about a dozen being about the size of a dime and two that are about an inch long by half inch wide. How do you repair these to prevent rust? Has anyone successfully used a porcelain repair kit and then painted? Is there any other kind of filler that can be used to make it smooth? I assume I can use high temp engine paint for the final coat?