Looking for cooling suggestions

I was on my way to a car show Saturday and noticed the temp climb from the usual 190 to around 210 while sitting at a traffic light.  This has happened many times before but the car never overheated then or now.  The traffic lights in Florida are usually very long.  The temp returned to 190 once I got going again.   When I was parking the car at the show the overflow spewed some coolant on the ground.  Later I checked the coolant level and it was full.  On the way home once again the temp climbed to around 210 at a light and dropped to 190 when I got going again. 

Speaking with other car buffs they suggested installing an overflow, installing electric fans, using a much less than 50/50 antifreeze solution and to use distilled water and hy-per lube.  I did some research online and it seems using some hy-per lube as an additive was among the suggestions and using some "Specially processed" distilled water was another.  Normal distilled water was said to be detrimental to a coolant system but using some specially processed distilled water was good.  Something about electrons ....  I didn't find anything about how much antifreeze solution to use.  I'm from the north and we always used around 2 gallons to be safe to around 30 below.

I feel that I should install a universal overflow tank and/or electric fans.  Not sure about how much antifreeze solution to use or if I should also use some additives. 

Is this a typical issue with big blocks and something I have to live with.  I know the car is not overheating now but I would like to insure it does not breakdown on the road because of long stops at traffic lights or in stop and go traffic.  I would appreciate any suggestions/recommendations.   


My car is a 65 Cutlass with a 455 close ratio m21 and 3:55 gears.  The car still has the original A/T radiator.


Thanks in advance for your help,
John