Re: runs on propane?
another thing that'll help.....heating up the full tank and cooling down the empty one. You prob can't do much about temperature and the stock tanks on the bus, but you can toss the bbq tank in a jacuzzi, or a hot bath tub, or wrap it in an electric blanket. You don't want it much over 100 degrees, so a jacuzzi is perfect...anyhow, this temperature increase makes more pressure inside the tank. Never use a flame or anything silly like that.
i'm also unsure if opd tanks will work up=side down.
Quis custodiet ipsos custodes (who will watch the watchmen?)