94 YJ Water Pump Mounting Bolt

I have a 6-cylinder 1994 yj that I am in the process of changing the water pump. Yesterday, I was bolting the new water pump on and snap, the longest bolt broke off inside the engine block. I barely put any torque on it. So my question is, does anyone know the size, type, where to find, etc. of the longest water pump mounting bolt? This really sucks! Thanks in advance.