I see from your post that both your guys are from abusive homes, well done to you for rescuing them first off.
I'm not sure what state yours were in when you first got them or how long you've had them?
I rescued 5, (2 tiels 1 ringneck, 1 red rump and a rosella) unfortunately the tiels and ringneck didn't make, they were too far gone. The red rump and the rosella are thriving. With them, at first, there were no bounderies, we had to work on trust, then getting them used to hands being in their cage (which used to mean bad news to them) I got quite a few bites I can tell ya. But over the years we managed to work things out and finally set some bounderies. I know this seems to be a backward way of doing things but with rescue birds the rules go out the window, especially with ones that have been badly abused.
Could you maybe tell us how long you've had them, how bad was their situation and what they will and will not tolerate from you. Also what boundaries do you want to aim for with them.