Working on a 26 T. Brass radiator shell. It was originally nickel plated but most plating is gone and what is left can be easily removed. There are a couple of tears in the top corners. I was able to solder repair these areas pretty well, but they still need a skim of filler. Is here any problem with the filler sticking to brass or solder? Of course, I think I should scuff the area with 80 grit before filler. I only have the one shell and don't want to experiment on it. Right now I have the brass pretty well polished up and it doesn't look too bad, but I would like to paint it body color. Thanks for any input.