i would make sure you bleed (burp) the system properly.
that hot water blowing out everywhere is sometimes caused by an air lock, where-by when cold/cool actually does start to flow through where the airlock is, the water hits the hot metal components and instantly boils and will shoot out.
this boiling and blowing normally happens when you take the cap off as this makes the cooler water flow through the airlock area Makng you think its a head gasket.
Put it this way, if it was a H/G and was that bad, i think your Oil and/or water would show the tell tail signs.
use a 2L coke bottle full of water to fill so the weight of the water helps fill the system better + jack car up as high as u can at the front, massage the hoses, leave cap off till water gets warm.
Have heater on hot and blowing too.
also on the drivers side hose, there is the smaller hose that goes from the radiator to the filler tank, take this off and let air bleed out, as much as you can until the water gets too host, yes u will lose antifreeze doing it this way too..