No start issue Im a little frustrated

Glycol doesn't extend boiling point. If the engine runs hotter than 180 with a 180 thermostat, you system is not able to expel the heat. Assuming your gauge is halfway accurate, start the engine cold and keep your hand on the upper radiator hose. You will know exactly when the thermostat opens, as the hose will get hot all at once. Look at the gauge, thats 180. Now take it for a drive at 35+ mph. If the temp keeps climbing, you have a radiator issue. Turn on the heater full blast, does this help? If so you need to take your radiator in to a radiator shop and have it rodded out. If you are running a slant 6 radiator with a V-8, it will probably heat up on you at idle no matter what. If you are boiling over, make sure the cap is new. If the system will not build pressure, it'll puke out coolant starting at 200 degrees.