New to site, new to Mopar overheating issues

i use the stock 340 rad with a big clutch fan with shroud and it never overheated even at 90 degrees sitting in traffic and the 340 was not stock . Since changing to a 426 stroker now using champion 3 core rad with shroud an clutch fan never gets hot ever . those flex fans are garbage , get a decent fan make sure the rad is in good condition and at least a 340 rad if original and you should be good to go .and an alu rad is not any better in y experience , just a lot cheaper could buy 3 alu rads for the price of a new old style rad
good luck , nice car !