Yes, this is indeed very tricky. The aging plastic also makes it a bit of a nail-biter as the piece is likely to shatter. I think I've tried using plastic spudgers (thin tools) to force the bar into place, but I've been curious if should be done at a more invovled stage of disassembly with the metal bar already attached to the door, and then the whole unit inserted into the back. This is really a long way of saying, I'm hoping somebody knowledgable chimes in. 😂