Broken water pump bolt removal

I snapped that same bolt off once and it snapped off flush with the block. I ended up taking timing cover off, drilled in center of bolt with 1/8" drill bit. Then I drilled a couple more sizes up but not big enough to hit the threads. Then I ran a tap through the hole to remove the rest of the bolt. When I got done the block looked like new. Make sure you put RTV sealer on those threads when the new bolt goes back in.