What is the uncontracted form of "won't ever"?

Solution 1:

Won’t is certainly a contraction of will not (well, actually, the earlier woll not) and all three sentences are grammatical, including the second one. Ernest Hemingway wrote in ‘Across The River And Into The Trees’:

I will get into the motoscafo . . .and . . . we will not ever see one another again.

There is no difference in meaning between the three, but each might be used on different occasions.

Solution 2:

The only contraction in that sentence is won't, which (always) means will not. None of the other words would be affected when you expand the contraction.

Thus, ...will not ever be the same is the proper way to understand this sentence.

That said, ...will never be the same is grammatical, as well. In speech, people either use the contracted version or the will never combination. Rarely do you hear someone say (in US English) will not ever.

All three versions, however, are grammatically correct and are identical in meaning.