Cant keep the car cool HELP

This is Starting to piss me off! i have a fairly well built 360 with all the goodies: cam, ported heads, headers etc. and i bought a new aluminum radiatior part# SUM-380459 thinking it would help manage the temp because before with the old stock radiator it would get reach 210 around town and on the freeway and once it was that hot there is nothing i could have done to keep it cool, NOTHING! but now that i have this radiator i am seeing the exact same thing maybe a little cooler on the freeway but if its a long trip it will get to that temp even on a cool day (70 degrees), and around town it will stay hot im talking around 205-210, the hottest its ever gotten i would say is 210-215. I already run water wetter, made sure that i diluted the fluids correctly, have a 180 degree thermostat, stock water pump and a Zirgo electric Fan with no shroud and it has a 3600cfm rating i am just confused to why it would run this hot these are some of the things we can rule out:

Timing is good
Fan is getting its 13v needed to pull in its 3600cfm
Diluted fluids correctly
fan is operating correctly as it should

Anyone in the same boat as me??? I am thinking maybe just change to a Mr.gasket/miloden thermostat and a Be Cool 13lb cap since a Stant thermostat is in it, and maybe flush the radiator and pray there is a air pocket in the radiator (but i doubt it). This car everyday has to face a 25mile commute so i understand 200 on the freeway is gonna be common but i know if i drive any farther it will reach 210 and keep on going

thanks a lot people i hope we can all figure out what the deal is so i can continue to enjoy my Mopar