@pigletto: When I see an item like that, I just jump into the box and sometimes I even get it, sometimes I die and get it unter the shield.
Aside from that - it "only" takes a lot of dexterity. For example you can wait until there is a good moment and then step on the small square above the bomb changers. Avoiding the baddybombs is very hard there (they hit me very often), but from there you can beat the two pears in the middle part of the level, and after you got them, it becomes a lot easier because all the enemies (or most of them) will be at the bottom of the level, so you only have to throw bombs at them

So in the end it is just training. I think 54.6 is the hardest Hell level until you reach the late Tuber's Tomb. 54.7 and 54.8 are similarly hard (okay, 54.7 should not be too hard at all^^ but for me it is

), then you can go far without losing too many lives.
(Okay, the one Howling Metal level with four bobbles and crazy white-blue bomb changers is evil too)