Yea, I used something like this.
http://image.made-in-china.com/2f0j00yeBEvNiCwOqg/Asme-B18-5-2-Metric-Round-Head-Short-Square-Neck-Carriage-Bolts-CH-bolt-011-.jpg
Once I had the hole drilled, I held the drill at an angel in the hole, to make the inside of the hole a little bit larger. So the...