What a nice letter you wrote! I can realte. I am 73 years old. I found my birthmother 20 years ago. It was hardly the idyllic relationship I had hoped for!...but nonetheless it was something that I am so glad came about.
In my case, the judge (I was born in K.C. Mo.) released by original birth certificate to me because of an ERROR he found on it... all I had was her name "Helen Wilson" and the state of Missouri to go on...but found her within a years time.
There are many more options available now...so GO for it... It sounds to me like you have your 'head on straight' and simply want to close that gap. To me, you have a RIGHT to do so! I think that ALL records should be made available when the adoptee is 21. IMO... If there is ANYthing I can help you with, I would be so happy to do so.
I have to add a little humor here... I first spoke to my birthmother the night of Halloween. That turned out to be rather appropriate...ha... but all is well. I wish you luck and love.