When I first saw the Japanese version of KKvsG, I was stunned at how much of Ifukube's wonderful score they cut out. He did some truly amazing work on KKvsG....but only Ifukube's Faro Island chant was left in the American version and the rest was replaced by cheesey American B-movie stock music.
Anyways, this film clearly follows
Godzilla Raids Again, with G popping out of the same iceburg he was buried in at the end of GRA. This is mentioned in the Japanese version, while the American version laughably acts as if this is the 1st time in millions of years Godzilla has appeared, yet refer to him as "Godzilla" as if they already know him (not to mention the helicopter pilot yells "Godzilla!" when he first spots him

).