If it is 2 disks, you have to install them both on the other identical server, lets the controller identified them as raid 1 drives, and try to boot.
If it is OK, you can remove one of the disks while shutdown the server,
try to boot from the other disk, after that install the removed disk on the old server, start it up, and it must boot.
Now to make a new image, just plug in a new disk, and the raid controller will recover the image on the new disk, to use it on another server, remove it while shutdown the server( so no head crash will happen).
Any way this procedure not recommended, and there will be risk, so try it first on test machine.