Propane outdoor fire pit plan

G'afternoon,
I would like to design a propane outdoor fire pit as shown in the picture attached:

-wooden basement
-"wall caps" table with patio slabs
-linear propane burner 6'' x 36''

I have a good idea how to do the conception of the wooden basement. But I have some trouble about how to make sure the burner is built in, giving a look like in the picture. I mean by built in that the burner is under the patio slabs.

Does anybody has a plan for a similar fire pit?

Hope it was clear

Many thx in advance.