You don't have to remove the barrel bushing for disassembly.
Free up the slide stop, then push the slide forward to remove.
I used a screwdriver to nude the guide rod forward and lift it up and back. THEN you can rotate the bushing without problem. BTW, its all gummed up with cosmo, which is why you are having a hard time moving it
The Yugo guide rod ain't made to be pushed, push the slide stop out then slide the slide off the frame, once you get the guide rod out then you can turn the slide bushing 180 degrees (all the way up) and then you can remove the barrel.