Per Randy, a few years ago:
"one thing you need to watch-out for is there are 5 Different Focus fuel pumps but ONLY 1 is the SVT Focus pump, so before you have it installed, make sure you got the right-one....Ford part # 3S4Z-9H307-BC, anything else is just wrong"
I don't know about part #6C34-9350-AA, but I believe if you're looking for a SVT Focus fuel pump, you'll need part #3S4Z-9H307-BC.