How do I choose which chao my AR chooses to transform.I wanted it to turn..

Well I just been recently getting the tails, amy, and kunckles chaos (which are immortal as well), anyways when you get the code from where ever if they say first slot, they mean the first chao you EVER had in that file, if you don't want to give that one up, the best thing to do is get another memory card and start a new file on there and take the first chao in that game(thats what I do). If they don't say what slot then if the second line is UUH7-P89F-K2602(since I've been doin it recently I remembered that line by heart) than it's the first slot one, if not that then it's probably for 2nd slot, they don't have 3rd and 4th slot I believe because those you would be from the hero garden or dark garden based on which you got first, if you even have it, so really you can't choose one sorry, it's just the first slot, just use a new memory card or take whoever your first/second chao is and change them(i did that to my second one cause it had like level 80's now 99s and I didnt want it to die)