Would you paint aluminum radiator?
been using aluminum radiators in front of my small blocks for over 10 years. Always painted the fins and what ever else shows through the grille black. Always had them cool better than the 3 core AC/340 stock radiators. Never had a cooling issue with them even with trans coolers and AC condensers in front of them. I drive the cars a lot in all kinds of conditions including the states along Rt 66 last summer in July