There wasn't any nudity except for a few background shots of breasts.
What happens is that the thieves tie people together after stripping them. So Sally Field takes off her dress, but grabs a large napkin or tablecloth and holds it in front of her. In the meantime, the thieves happen to pair up Michael Caine with Sally Field, but Michael Caine resists, and gets hit on the head. When he wakes up, he's tied to Sally field (belly to belly) and the napkin/tablecloth she had is on his head wound.
She's very embarrassed, and keeps on shoving her forehead under his chin so that he cannot look down. He on the other hand is honored, because she gave up her last piece of clothing for his sake.
The scene ends with Sally Field telling him "just don't move." <pause> "I said, don't move!"
"But I have to breathe."
"You don't have to breathe with THAT!"
I don't have any vids of this. Sorry.