In a song I was listening to, there was the sentence:
僕はE缶だけは最後までとっておく
With the given translation:
I will only take the E-Tank at the very last moment.
I don't understand why だけ comes before は, since は seems to apply to E缶. It seems strange to me, I would expect: E缶は, i.e. I'm going to say something about E缶. Which is the case in the song. But with E缶だけは it seems like something is said about "only E-can". i.e. "I will take only the E-can at the end", instead of "I will take the E-can only at the end". Where the thing that "only" applies to changes.
Why does だけ come between は and the noun? Is this perhaps something that is done to make the song sound better?