at the top of the page here it says *settings*
click on that and you come to an empty box
type in this*< center >* but without the stars and the spaces,so the arrows are right up to the word then copy and paste the middle line from pb (tag line) like you do already and put it next to the center.
that should work for you.
so you don't have to keep going to pb to put your sig on here it will come up after each post automatically.
hope that makes sense! :-D