Hurricane Burner/Natural Gas burner distance
 

So, my beautiful girlfriend got me a hurricane burner and a natural gas converter for Xmas, it came a bit early :)

I am going to build a brew rig, sometime in the near, probably far, future so she got me the one without the stand. I can weld so no biggy, but curious what folks recommend for the distance between the burner and a keggle?

Is it one of those things thats standard or based on how much pressure my pipe is pushing out?

Thanks for all advice.

Conventional wisdom seems to suggest between 3-4", based on 80K BTU burner.