Just finished replacing the water pump on my 98 SSEi. Had to remove the engine mount and supercharger idle pulley to get that last bolt out of the block. That'* crazy!!

I had a water pump stud left over from a Ford 351. {first pic) They are available at any parts store.
I ground the hex off the stud with a cutting wheel on a 4" grinder then chucked it up on the drill press and ground it down so it looked like it was never there.
I threaded the stud into the block then installed the water pump as usual.
Now when I want to replace the water pump in the future all I have to do is remove the nut leaving the stud in the block and the water pump can easily be removed. That should save alot of work (and time) the next time it needs replaced. The original water pump lasted 218,000 miles. the replacement parts never seem to last as long as the originals.