Can't really answer the question about the high pressure stuff. BUT when I ordered mine, there was a drop-down type dialog box that let me pick propane or NatGas. I forget the specifics right now, but I do believe my burners are intended to Low pressure Propane gas.
As far as the burner height, the answer is, YES I am using Lonnie's plans.
My friend, who runs the company that employs the welder, was thinking, that, since I ordered 2 of the control panel 12x24 sheets instead of a different sheet of steel to protect the pumps, that he could use a piece of "diamond plate" steel to cover the pumps and take the second Stainless sheet and make 4 inch wide strips that act as a stirrup for the burner, welded to the frame at the top, and upon which the burners rest.
A 4 inch drop plus the 2 inch thick tubular steel is a 6 inch drop. The burner tips are about 2.25 inches from the bottom of the cast "ring" of the burner. Add another 2.25 inches and that is 4.5 inches. Minus the the 6 inches means I need 1.5 inches of shim to boost the burners up a bit if they are really going to be resting on the support "stirrup". This does lend some flexibility in my design, particularly if I use flex tube to supply propane to the burners. I wonder if there is an easy way to weld a bracket on the SS "stirrups" running front to back so that I can more easily adjust burner height perhaps with a friction screw or something (like the neurosurgeons use to keep people's head in those shoulderpad HALO harnesses).
Anyway, probably making it more complicated that it needs to be. Thanks Lonnie for the 2.25 Spec!
One other issue I have is making the control panel. I often let the boil run unsupervised with a few drops of FermCap to prevent boil-overs , even under windy conditions (I have a flame shroud on my current burner). I'd like to keep this trend going with the brutus and the spark ignition modules will serve the same purpose, though NOT for the boil kettle. GOing to need a shroud for that burner... Anyway, I was thinking about how to seal the front flat SS control panel. I can only think of using automotive gasket material and applying a box to the back with screws....
I need to draw up a pencil & paper plan for the control panel for the shop to cut out the panels. Using the same basic Lonnie design, but using different temp controllers with larger cutouts. 45mm square holes for these....
Thanks for all the support on this site!~ Its been great!
TD