Check my math.
She was born in Oct. 1964 and this film was released in May 1982 according to IMDb. That’s five months before her 18th birthday.
So she was 17 during filming, including her full nude scenes.
It’s also not her first nude scenes. She was fully nude in Laura in 1979 when she was 14 or 15.
This site says she was born May 17, 1963:
https://www.celebsagewiki.com/dawn-dunlap
This site say she was born January 1, 1964:
https://www.howold.co/person/dawn-dunlap
Did a search and it’s either ‘64 or ‘63 on different sites. Wiki, who is usually spot on, doesn’t have it.
This article mentions photographer/filmmaker David Hamilton took her to the Bahamas to pose in 1976 when she was 12:
https://maxstolzenberg.com/2021/01/26/another-sip-of-sunshine/
If that’s the case, that puts her birthdate at 1964.
Thing is, she’d look the same whether she’s 17 or 18 so it doesn’t matter. It’s just a date on a calendar.