Gas Line Plumbing
By hard plumbing the gas lines on my brewstand I can fuel the entire system with only one propane tank. With three gas valves attached to pipe tees I can run any combination of all three three burners at the same time. The connection from the burner to the gas line might vary depending on the type of burner you buy, the burners I bought from B3 come with el cheapo 90 degree angled jets that are known to break. B3 custom fabs their own straight jets that are much stronger (available here really cheap). B3 also sells the adapter to couple the jet to the gas line assembly (see 2nd photo for jet and adapter).

Gas line is 1/2in black pipe, here are the parts I used:
3 burners
2 straight pipes, threaded on ends (I had these custom cut and tapped (or is it dyed?) for real cheap...they do it at my local hardware store
3 pipe tees
3 gas valves
3 90 degree pipe elbows
3 custom jets
3 adapters for jet to gas line
1 pipe closure for gas line (left picture)
1 flare adapter
1 adjustable propane regulator

One really important thing I would mention is that you should have some sort of horizontal support under the burners. Technically the strength of the gas line will support the burners, but it makes the weakest point in the assembly the jet. B3 actually sells several of its sculptures this way, but they recommend a support if you are doing it yourself (see 3rd photo for burner support).