im going 3/8 too . i just bought that unit. What a deal. ive got my stock gas line on now. What are all the beneifits of going 3/8 to grom 5/16. Do I have to put a whole new line in now? Thanx for the the link. Ive got my tank out now for a restore, and paint. I dont think that unit comes with a new lock ring though. i did see a cool lock ring spanner wrench on ebay though.