Just don't do what that article in the link tells you to do, e.g. DO NOT "ZIP TIE" the resistor!

It gets VERY HOT and will melt the plastic.

I used metal heat sinks affixed with bolts to the side of the case and held the 10w resistor in place with a metal loop.

After years of use the heat sink looks like it's a bit burned, but otherwise everything works great.