340 coolant trouble

No guages so far. Sorry, it took me so long to reply. Blew the top hose but it was old. Put a new hose on and it overheated and bubbled up through the uncapped radiator. Pulled the new thermostat and put another new one in just in case. Still bubbled up through the uncapped radiator. Pulled the thermostat to see if the radiator would show some flow. Burned the coating off my brand new 700.00 dollar tti headers.