No ac, so no condensor, the carb is a holley 650, and the distributor is a gm hei with a hypertech hi volatage coil and cap. it has hooker shorties which probably add to the problem a little. and the radiator came out of my 78 monte carlo which had never overheated even with a bum 305,(engine died of oil contamination due to massive blowby). the monte had the exact same fan shroud and flex fan. zero overheating problems on that car, and reamed on that thing hard,real hard, in the high temps of summer, about 90* ambient temp.
The fins were fine upon original inspection. no blockage.