I have a 67 Cuda convertible, and I am starting to get asked to be in parades a lot to represent the Midwest Mopars club, and by a friend who coordinates a parade. It has a 273, and it overheated in my first parade last year.  So This year I put in a 16" SPAL electric fan (I think 3300 CFM), and removed the fixed fan from the engine. I also had put in a 180 deg thermostat, and still noticed that I was overheating, tonight I put in a 195 degree thermostat as was suggested by the SPAL guy, but that made it overheat even faster, and stay overheated longer, when just cruising around town. This will never work at parade speed.

I noticed that when It gets warm, the middle of the radiator is cool, but the top is too hot to touch, and that the antifreeze rises from the opening in the top of the radiator filler hole when the cap is removed.

Could it be that my water pump is not pumping?? Or should I put back the 180 degree thermostat?? Or is there something I am missing?

Thanks  

I dont run a thermostat at all in my motor and run two 3000 cfm electric fans with a crossflow aluminum radiator.  I have never had cooling issues.  I also removed the belt driven fan and have my two electrics on either side of the radiator...one pushing and one pulling.  

How long since you have had the radiator "cored" out and pressure checked? I would suggest taking it to a good local radiator shop and have them clean it out good. They can remove the top and clean out the water flow cores. Also make sure the fins are fairly straight so the air will flow through them properly. My 72 340 had the same issue and that problem is now gone!  

Its a rad issue, the fact the rad is cool in the middle suggests there is blockage in the rad, it will likely have to be replaced. However having the rad boiled out at a rad shop sometimes helps for a short period of time.
No idea why someone would tell you to put a hotter stat in a car that is overheating.
Electric fans used as pushers in front of the rad are fine but I would run the reg. belt driven fan as well.
I run this set up at the track, a clutch fan with a pusher in the front, the pusher comes on only in the pits when the car is sitting or idling, this helps keep the engine cool and gives consistant tempetures ready for the next round.