Steel Guitar Builder

I am thinking about changing the key heads on my GFI student so I can go to better tuners. They are 1/2" x 3/4" bars. What would be the best type of aluminum to use? I probably will polish them instead of painting them crinkle black like GFI did.

6061-T6 Aluminum is the most commonly used on a steel. Most readily available as well.

Thanks Bent, that's what I was thinking, just wanted to make sure.