I am surprised there are no comments in English. I agree with all the comments that remark on the excellent band and singers. They are top notch! Very good. Perhaps one day I will find this film. It looks like fun.
Chiemi Eri sang "Come On-A My House" in at least three different films - that's how popular this song was in Japan. I figured out what was happening here. Chiemi was at the movie studio filming a scene in blackface while this performance was going on, and everyone was worried she wouldn't get there in time. So Frankie Sakai did a long drum solo which allowed her enough time to jump in the Ford and take off her other make-up, and then arrive to sing the final song.