LPG regulator installation.
After much search I located the regulator that I was looking for at go2marine.com, 800 998-9508
The regulator is Dickinson, Low Pressure Regulator part no 78177 for $ 15.69. I also ordered the Tank Fitting part no 318548 for $ 18.10. It included an elbow that I did not use. Instead I baught an elbow from Home Depot for $ 4.85 and teflon tape for $ 2.95.
The installation took about an hour.
The problem was that there was not much room to work in, but it all went together fine.
I pressure tested using dish washing soap and a brush.
I learned that the regulator must always be above the liquid in the tank. If the liquid propane pours out of the tank and ends up in the regulator, the regulator will be damaged.

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