if you stand on the upper left side of the box you can bomb down the lemons, pears, and the blob. by the time they're down you've probably killed quite some enemies at the bottom which makes it a lot easier. another trick is that you can stand inside the left teleporter and if you kick a bomb it will get inside the box, you have to be very careful not to get hit by a pear's bomb, blobs fire, or bombino blast though, but usually this isn't the best way.. both 54.5 and 54.6 i've succeeded to complete only once without dying without help.. good luck
