It won't catch. The flap is articulated exactly the same way the mk43 and 45 are. It's in that pose already as far a the legs are concerned. To get from the photo to the fist touching doesn't require moving the section your worried about at all. Really, it can do it.
And I don't know what other people did..but I can get the original Mk3 I'm the pose without popping anything off.
In the photo I posted the leg is not popped off.
You may not have noticed but those hip flaps are not one piece and are double articulated. The front red part moves separate from the back red/gold part and can move over top of it.
There's more then enough articulation and it's probably better then the 43.
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