The biggest problem ( I see ) with it running a bit warm all the time, is there is less room for error should you have a problem. I.E. if you gain a mere 15-20 degrees you are boiling over. I have been working on the 350 in my 64 C10 off-and-on for about three years now trying to get rid of its heating problem.

The current set up includes a Summit aluminum radiator, with an 18 inch electric fan in front. ( pushing ) Also, have an oil cooler, about 8X10" which sits below the radiator. On the road, with 90 degrees ambient, it is now a cool 180. Still plan to make a couple changes though: going to put a themral switch in line with the fan relay to shut off the fan below 170, and add a small fan to the oil cooler as the temp still climbs up a bit at idle. also need to make a stone guard for the oil cooler using some expanded steel.