Maybe they meant to print "post" but it does read "plate". If weigh of the door is on the latch post the sheet metal post is in will crack. We've seen it many times.
"Lowering outer end of door moves lower part of door into door opening". Whut? LOL
I go at it with my carpenters hat on. The door closes aligned the jamb/opening before the hardware, in this case latch post, is installed. The big difference is the carpenter can adjust the jamb/opening. Our only adjustment is at the door hinges. Those bolts are challenge to access. The assembly line workers would hang/align the doors before the fenders were installed. We put much more attention and time into such details than they ever did. Good luck with it.
