I-6 engine temp question

[Knoxville71shortbed]

I finally installed an aftermarket temp gauge in my truck, because I only had the idiot lights, and didn't trust them. I have a stock, good running 250 I-6, and have been driving this truck daily for almost 2 years (100 miles per day). In the summer, when it was over 90 degrees and I had been driving for 45 minutes or so, the temp idiot light would come on briefly at stop lights, and then go out when I got moving again. This is what prompted me to install the gauge. Now that I have a gauge, I'm not too sure what a good operating temperature should be for this engine. It seems to run at around 230 to 240 degrees. Is this too hot, under normal conditions? I have installed a new radiator, and like I said, the engine really runs good. I'm just worried about long-term problems from high engine temp. Am I worrying over nothing? What would you recommend to bring the operating temperature down? I haven't replaced my water pump. It shows no signs of being worn out. Could it be that it's not moving the fluid fast enough? I set the timing by ear, since the polution control garbage has been removed (it's a 71, which originally had an air pump). It starts easy, and runs great. Could the timing setting be causing the engine to run hot? The I-6s did not come with a fan shroud. Should I consider installing one. Or am I just paranoid? What do you guys think?