When the guy came to install the gas tank he said that we should use the gas in the old tanks and then I can just change over to the new tank when the old tank ran out. It did involve soldering the copper pipes which I thought was the difficult part.
What the gas guy failed to notice was we needed to connect a 1/2' fitting to a 3/4' BSPT fitting. So it was a freezing cold, rainy sunday afternoon when we ran out and I realized I needed a reducing fitting in order to connect up the new gas supply. None of the shops where open and my neighbour Terry didn't have anything to do the job so it was 'boer maak n plan' time.
There was a plug fitting that the installer had left in the pipe to stop dirt getting in. I used this to make a connection on the 3/4 side and turned down a brass fitting off an old braai to connect to the copper pipes and finally got the gas flowing.