I'm getting HOT!!

[flyboyjack]

Well, I tried searching for answers. Couldn't find what I wanted/needed. I have an all original 71 C10 and 350. Temps are fine when driving, but get me stopped at a long light or worse, stop and go traffic here in southwest Florida and in a matter of a few short minutes, and I mean SHORT, the water temp goes all the way to the right. It doesn't knock, but if I shut down it of course gets hotter and will "buck" a little on start up. As soon as I start moving even 15-20 MPH, all is well. Original radiator. New cap. New 160 thermostat. What am I missing? Got 100K on the engine. Remove and clean the radiator? Change fan blades? I would like to stay "old school" and not go electric. Help please!

Thanks