Bocca GCC used to be a huge biter and totally afraid of hands. Over the last year I have retrained him to tolerate hands and literally forced him to endure being petted while he was trying to hide from me while on my chest. He has become so fond of individual, one on one attention he rarely leaves my body when he is out of his cage. His favorite place to perch is the top of my head and when he wants a nap, he wedges himself behind my neck and I can feel his hot little breath on my neck while he sleeps. Bocca will still attack hands, especially if they are not my hands, but he has no stylus on his upper beak, so all he can do is pinch rather hard.
Bocca and the lovebirds feel my head is the best perch in the room.