With a bladder or diaphragm style tank you don't need the bleeder, above ground check valve, Schrader valve, or AVC. These are the moving parts that usually give problems and are not needed with a diaphragm tank.
If you have a bleeder down the well, hopefully it will stop bleeding when you remove the above ground check valve. As long as there is pressure on the bleeder it won't open, and therefore won't need to be removed. But if after removing the above ground check the pressure bleeds off when no one is using water, the bleeder is not staying shut and will need to be removed and plugged.
Here is an animated video that I hope help answer some of your questions.
[ame]https://www.youtube.com/watch?v=LPIUufWjbic&list=PLpIZn7LpzYEABUoA0UZPhQkMvT9vUN75H[/ame]