You have memorized your monologue. You came up with for your song and can deliver it expressively and in a way that is authentic to your context. Now you have to sing it. How does all this work apply when singing with the original text?
Don’t get rid of anything you worked on.
Sing with good healthy technique. Sing the correct notes and pitches. Be true to the style you are choosing. But really the only things that should change is that you are now changing what your mouth says, the specific pitches it says them at, and over specific durations. Don’t change what you do with your body. Don’t change what you think in your mind.