I feel like that's the same thing we all fight with at the beginning of our transition. The important stuff to know in my opinion are:
1. Go at your own pace. Dont feel pressured to leap in, unless you are used to that method.
2. Transitioning, at an older age, is a second puberty. We experience changes in our bodies and deal with new insecurities. These are all things that fade with time.
3. After starting that journey, things may start poorly, but they get better. It may start slow at first but will gain momentum later. Make sure to surround yourself with good people. It helps.
The last thing I have to say is that I too used to do a lot of body building and bulked up, I'm 6'3" too. I even got the "oh you wont make a pretty women", bit. That said I think Ive turned out alright. I can send you before and after pictures if you're interested. Tall girls are exotic and sexy btw. Don't let the social norm tell you otherwise. You got this girl.
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