(at around 52 mins) The magazines shown in the montage following the Dream's first performance are all dated in 1964 and is then followed by a 737 jet taking off. However, the 737 did not enter service until 1968.
Just before the gospel break of the "Steppin' to the Bad Side" number, a medium shot of the Dreamettes features Deena on the left, Lorrell in the middle, and Effie on the right. The shot immediately following is a long shot showing the full stage, with Effie now on the left, Deena in the middle, and Lorrell on the right.
The Dreams' success montage includes a picture of the trio standing on the Great Wall of China. While the U.S. and China had no diplomatic relations from 1949 to 1971 (Washington had ties with Taiwan instead), there were numerous cultural contacts between the two countries in the late 1960's, not least because China and the USSR were having strained relations and China wanted to improve relations with the U.S., and having a famous group like the Dreams in China would have been very possible.