In particular, you should refer to Chelsea as she would want -- with her current name and her expressed gender pronoun preference (e.g., use 'her' where you use 'his' above). Also, "gender association" is not a common formulation.
In terms of capturing the nuance of acts prior to public transitioning, the above link has some suggestions:
Avoid pronoun confusion when examining the stories and backgrounds of transgender people prior to their transition.
Ideally a story will not use pronouns associated with a person's birth sex when referring to the person's life prior to transition. Try to write transgender people's stories from the present day, instead of narrating them from some point in the past, thus avoiding confusion and potentially disrespectful use of incorrect pronouns.
I suggest reading http://www.glaad.org/reference/transgender for more context.
In particular, you should refer to Chelsea as she would want -- with her current name and her expressed gender pronoun preference (e.g., use 'her' where you use 'his' above). Also, "gender association" is not a common formulation.
In terms of capturing the nuance of acts prior to public transitioning, the above link has some suggestions: