DEAR JUDY,
My guess: The actual subject of the sentence is the pronoun
"us" with the verb "go". With poetic, emphatic, redundancy, TS
uses "you and I" to refer back to the subject pronoun "us", all of
which take the nominative case so you and "I" would be correct. Am
I close?
Another case in point, "A preposition is a bad word to end a
sentence with".