You are drawing an analogy with the Stevie Wonder example. the analogy is that the existence of your God is to me in the same way that color is to a blind person.
CONGRATULATIONS! A big thought finally kicked in and you got something right.
That analogy only holds if your God exists entirely in your imagination or is incapable of affecting the real world.
Aw, and you were doing so well there. Let me dumb it down to your fake big thinking level:
Fire engines are red.
Stevie Wonder cannot have that DEMONSTRATED to him.
Nevertheless, fire engines are red.
Stevie is not so dumb as to claim:
"Since you cannot DEMONSTRATE to me that fire engines are red, THEREFORE red fire engines are IMAGINARY."