He has happy eyes and is doing things no bird would do if they didn't trust the person they are with. It took about 5 years for Lurch, a used Parrot with baggage, to fully trust and love me in his own way. You can see it in his eyes and body language in the later pictures I have of him.
Your guy is happy to hang out with you, cuddle with you, snooze on you. A concerned, scared bird would never do that.
It's a gift they give you when you earn it from them, he'll be a loyal friend for his the rest of his life.