Removing hips

I'm new to removing elite legs for customizing. I had pretty good success removing them from the Lost Legends Taker and the Elite modern Hogan. I use a hair dryer rather than boiling water as some do. But I am having a hard time with elite Neidhart - just the hip joints. They just don't seem to want to pull off. Is this perhaps in any way related to the new hip ball joints I have read about on here or is it unrelated? I'm not even sure how to tell the difference between the old and new ball joints. Thanks for any thoughts.