Door question

[mokie]

The plate that is inside the body, where the door hinge bolts connect the to the body. Where can I find that piece and how do I keep it from moving? right now it is unstable and I believe that is why my doors, fenders, and hood does not align together.

I checked out LMC but nothing is there. Also, how do you get in there to replace it?

Does the movement of this piece affect the outcome of the door, fenders aligning?

Thanks