How many movies have Akira Ōizumi and Go Nagai collaborated on?

They have worked on 6 movies together! Their first movie together was Shameless School (1970) while their highest rated movie together was Kekko Kamen 2: We'll be back... (1992). They have not worked together since Kekko Kamen 3 (1993). They are most known for their comedy films together.