Please help me with these sentences (Past Perect)

[Helen]

Please help me with the followingsentences. Which is correct?
1. Before we had driven too far we found out that we had taken the wrong road.
2. Before we drove too far we had realized that we had taken the wrong road.
3. Before we drove too far we realized that we had taken the wrong road.
That is a sentence from a grammar exercise where I am supposed to use the Past Simple and Past Perfect Tenses.The more I think, the more confused I get.Please, help.

[Mister Micawber]

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#1 and #3 are OK; the teacher probably wants #3.
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Native English teacher at Mister Micawber's

[American_Expat]

Agree with Mister. Both 1 and 3 are acceptable, but since the exercise is past perfect, 3 is the right answer.

[Helen]

Thank you for your replies.
Sentence #3 is quite safe: two actions follow each other.

My doubt regarding sentence #2 is this:
We had realized earlier than we drove too far (Isn't that the meaning of the whole sentence?) However, the sentence, is really "clumsy".
So what comes first: "our realization" or "driving too far"?

[Mister Micawber]

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Go with the logic, Helen, and the grammar usually follows. In all cases here, the realization comes before driving too far. 'Before', however, essentially pre-empts the need for and use of past perfect.
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_________________
Native English teacher at Mister Micawber's

[Helen]

Thank you, Mister
Your explanation is very helpful
I got confused because I saw some strange logic in my students' answers when they came up with the second sentence (Before we drove too far we had realized that we had taken the wrong road) though it did not agree with my understanding of grammar. Coming back home I started to search the internet and found this forum.
In fact that is my first experience with a forum, I have never tried that BEFORE!
Thank you