Thanks! That second-to-last link showed how to use the post # to do what I was trying to do.
Btw, using the format of the third to last link only works for the first page of a thread. It always loads the first page of a thread, as far as I can tell, so if the post isn't on the first page of the thread it doesn't load the right post.
But that second-to-last link format works no matter what, regardless of the number of pages in a thread
