i used 1/2 copper pipe soldered together with 4 ports two each for the pilot light and main gas line to the burner. needle valve on the pilot going to a 1/4 in copper copper tube bent to line up with the burner and crimped at the end. the for the main you can go with a standard gate valve but i used solenoid valves and then gate valves for metering the flow.
i would not splice rubber hose, i had mine cut and crimped at a local hose shop and at $4 a hose it was a great deal.
people get scared of propane but as long as you're leak free, test by pressurizing your system with air and squirting joints with water, you're fine