This Koyo radiator is specified for 1968–1972 Nissan Skyline KGC10 with the L20 inline-six and manual transmission; installation requires SK-C13. It serves as the dedicated cooling core for that chassis and engine combination, replacing the factory radiator with a direct-application part that is identified for the KGC10 Skyline L20 I6 MT fitment.
Koyo 68-72 Nissan Skyline L20 I6 MT (KGC10) Radiator (SK-C13 Required)