How to change a pivot point in MsPhysics?

[madsnilsson1000]

Hi and thx for letting me in. I guess this is really easy to do - but I am not that skilled. I try to make "a box" with a top lid, when opened, pushes a bottom lid out. I need to pivot the point of the top lid around midpoint, so it touches the base and pushes it out at the same time. Hope the video makes it a bit better to understand. Thanx a lot - best! (MsPhysics). In the attachment section is a clearer picture.

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