I just read this post and think your helmet looks great. But like you I bought a black Sam Houston because of the price and needed to paint it yellow. I used hight heat engine block paint primer. It looked really good after I thought smooth and glossy. But didn't take long after a few fires it cracked and chipped like crazy. A guy at my house has a factory job. The oil based sherwin Williams paint and it doesn't chip nearly ad bad. I just repaint mine again and this time I did a total strip and used the right type Of paint. I'm sure it doesn't matter but maybe it'll last a bit longer.