I think (but I'm not sure, not having read the story lately) Darth Michael's excellent
"Don\'t You Dare" has the revelation happen that way. Advisory: it's steamy hot nfic.
And I think Carol M's fine
"It\'s A Big Bed" has the same thing.
Note how both these "Lois sees Clark floating while he's asleep" stories are based on "Honeymoon In Metropolis". That would seem to be a natural correlation of the dialogue: "It's a big bed." "We could share."
I'm interested to see what you'll do with this different episode. Clark floating in his sleep is something which can't be explained any other way except by understanding that he is Superman. Although I'd like to see him use Marcus's suggestion and try to tell Lois that like the people in "Ghostbusters", he's possessed. But I think she wouldn't buy that.