I think you could so long as you include an addendum describing what you did here and that your identity comes from a desire to connect with what you think is your racial heritage. I think its important to point out though that you were raised white and this indenity is a rather recent, but sincere choice rather than the way you were brought up. There was a poster name Bigtex a few years ago who had a similar situation, lots of drama ensued around him though.
Being adopted myself I can empathize about your wanting to know your roots. Unfortunately I was adopted from the hospital anonymously so I donít have any info at all about my birth parents, but I do sometimes wonder who they are what they are like. But Iím white, raised by white family, so no real identify issues other than curiosity sometimes (though not often, I consider the parents I have the ones who changed my poppy diapers, raised me and bailed me out of jail to be my ďrealĒ parents not the ones that just spent 9 months carrying me around).
Good luck with that. Just be sure to make it clear why you feel the way you do that way no one can come back and attack you for it. I think identity, especially for adopted people can be created, because we never have a complete connection with our birth parents, there is always that wondering in the back of your mind would I be a different person than I am now if I was raised by my birth parents?