Take it from the guy that should have known better but didn't. The bottom water pump bolt has to be no longer than the one you took out. That's the one nearest to the fuel pump. A bolt that is too long will get hit the first time the pump arm moves. I only made this mistake twice. I didn't have a clue what happened the first time. The second was many years later.

 

That's about two times less than I make most mistakes