Well, I think I am to that stage in the build that I need to ask the fatal question about plumbing LP.

I have a heater and a Norcold 2-way refer that both will be piped with LP.  I have them stacked on top of one another using a shelf for spacing and to give the right amount of clearance for air circulation but haven't really figured out how to plumb it yet.  has anyone done it before? 

Did you use black pipe from the tanks, maybe a copper or flex hose??  I am really lost and thats all I need is to get this far and mess this up and die of CO2 or LP poisoning.

any help would be great

PS  if anyone needs a extra set of Norcold refer vents, I have an extra set (company acidently sent me 4 instead of 2)