Burner to Kettle Distance

I’m in the process of having a brew stand built. What is a good measurement for the burner to bottom of  the pots or kettle. It’s going to be a two tier stand and the guy thats go to weld it up needs to know.
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Thanks
Bob
www.hellgatehomebrewers.com

What sort of burner do you have? It depends on the size/height of the flames. You’ll want the “cone” or hottest part playing on the bottom of the kettle.