Electric VS standard fan

I have been trying to fix over temp problem with my 71 Duster for a year. I have new engine-- 500 miles on it maybe--3 core aluminum radiator--26"x 16".The radiator does not fit into the cutout in the radiator support and therefore is mounted on the back of the support and has only 2.5" clearance to water pump pulley. I have tried 5 different electric fan combinations and cannot keep this engine cool in traffic in Florida in the summer. Last dual setup I bought was a Spal dual fan with dual 12" fans that were supposed to pull 2800 CFM and I was getting the best results with that setup but still hitting 230 when I checked it right after shutdown. I bought the baddest dual Spal fan available--but need 3.5 inch clearance to install. I'm done with electric fans I think--going to buy correct size radiator and go back standard fan and shroud. I probably spent $1500 on electric fans and just give up. Anybody want to comment. Motor is built with no expense spared and temp is OK driving on the interstate but in traffic it heats up and takes 10-20 miles on the interstate to cool down. Somebody talk me out of going back to the factory setup. I'm well versed on cooling problems as I also have a Pantera--which is notoriously hard to cool--worked that problem out quickly with a set of Spal shrouded fans that were over $700 and it stays cool in 90 temps without even turning on the second fan. Somebody talk me out of going back to the factory setup.