1999 Daewoo Leganza head gasket problem

I received an answer to my original question, but yhe thermostat snf the water pump were replaced. I answered blacktop with this question, but he emailed me to do it in car repair question. So I am. Hopefully he can help me. They tried to fix it again without tearing down the engine (which they don't want to do. Any help please. The car gauge shows 3/4 hot and I am afraid to drive it anywhere far because I do not want to absolutely ruin it. Please help.