I am the owner of several old Marx cars in various conditions. Some of the wheels are just covered with crud; make that Crud. I started with a bright boy but could see where the pyramids would be even smaller by the time I got done. So I put a wire brush in the Dremel and carefully used it to remove said crud. Is this a heresy in the wheel cleaning sect? What other methods are in use. I know one shouldn't let the wheels get so dirty but this dirt was decades in the making and not all by me. Thanks.