In several scenes, women are dressed in what appears to be skintight flesh colored fabric. This fabric is tight enough to give off the illusion of nudity, especially in the rear. Nipples are "visible" in the form of pasties and questionably small amounts of glitter. The women's crotches are covered in little more than decorative golden leaves.
The NR rating was most likely only because of the women's outfits that are 1000x more revealing than those in Jesus Christ Superstar (G), and they even "show" the nipples in this, but behind pasties and glitter.
Men are frequently shirtless.
Women frequently wear clothes that are tight and reveal some skin. Nothing explicit.
There is one scene where Joseph's master's wife is said to "see a lot of men against his [her husband] will". She tries to seduce Joseph by telling him to lie down with her. He resists. In this scene, the women wear revealing clothes that appear to reveal their "breasts". It is actually tan material (like worn by figure skaters) with glitter where their nipples would be.
In the scene where the Pharaoh sings Joseph his dream, there appear dancers in very thin blue bodysuits, thin enough to make their backsides quite prevalent.