Depends on your emulator, and on your programming skills. Atari++ offers the option to install the H: device handler under the D: name so you could use that transparently; first use the DOS of your choice to copy the contents of the AMS .ATR image to a H: device, then install the host device as D:.
Second option: IIRC, the AMS player is simply a basic program that bootstraps the assembly language player. Load that file under basic and modify the D:s to H:s.
So long,
Thomas
The emulator I'm using is Atari 800 Emulator 2.0.3, I don't know how to really how to use Atari++ (did download it) nor how to do option #2. Thanks...
Thanks