Anyone hook up directly to your LP tank for a grill?

I have a 1992 Ford Tioga with an older but fully functioning LP tank. It's 14 gallons I believe. I want to hook up a grill to it. Oddly enough, there seems to be a connection for a 1-20 hose (used to go to a grill) right on the tank. Does anyone else have something like this? I've looked everywhere online and I can't find another example of an older tank that has a connection like this. Is there a specific 1-20 hose that will hook into this? It seems to be a female connection but it is deeper than a normal 1-20 hose could reach. Anyone have experience with this and know what hose I need to get?