82. During the date at the end of "Individual Responsibility" where Clark promises to be there at 7:01, 7:02, 7:03 etc., he obviously stays, we can infer this because they are on another date when "Whine, Whine, Whine" starts.
With the level of crises during that time, it is clear that Clark skipped needed Superman rescues for it to work, or at least we will assume this for the purposes of this section.
So Lois figures it out when she hears about a crises Superman was needed at but skipped, and so she thinks about everything, including how Clark's vanishing so often correlates with Superman being needed, and she realizes SM=CK.
83. This requires a little change. In this one Lois actually sees Superman in his police office uniform. I am pretty sure we are not shown such a scene in "Church of Metropolis", but it would not be that hard to infer such a scene somewhere.
Then when Lois sees Clark in the army officers uniform (that among other similarities also involves a hat), she realizes how much he looks like Clark the officer did, and thus that SM=CK.
